Abstract

We demonstrate optical manipulation of structures and defects in liquid crystals (LCs). The effective refractive index depends on the LC molecular orientations and the laser beam’s polarization. We use the orientation-mediated refractive index contrast for the laser trapping in LCs with a homogeneous composition, but with spatially-varying patterns of molecular orientations. Tightly-focused polarized beams allow for optical trapping of disclinations and their clusters, dislocations and oily streaks, cholesteric fingers and focal conic domains, etc. We calculate the optical gradient forces for typical structures and explain the trapping properties at low laser powers. We also show that when a high-power beam causes local molecular realignment, the laser trapping properties change for two reasons: (1) the refractive index pattern and optical gradient forces are modified; (2) additional elastic structural forces arise to minimize the elastic free energy.

© 2007 Optical Society of America

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  5. Y. Roichman and D. G. Grier, "Holographic assembly of quasicrystalline photonic heterostructures," Opt. Express 13, 5434 (2005).
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  6. T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
    [CrossRef]
  7. I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
    [CrossRef] [PubMed]
  8. M. Yada, J. Yamamoto, and H. Yokoyama, "Direct observation of anisotropic interparticle forces in nematic colloids with optical tweezers," Phys. Rev. Lett. 92, 185501 (2004).
    [CrossRef] [PubMed]
  9. A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
    [CrossRef]
  10. I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
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    [CrossRef]
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    [CrossRef] [PubMed]
  13. I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
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  14. I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
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  16. S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
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  22. P. Steffen, S. Wurlitzer, and Th. M. Fischer, "Hydrodynamics of shape relaxation in viscous Langmuir monolayer domains" J. Phys. Chem. A 105, 8281 (2001).
    [CrossRef]
  23. S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
    [CrossRef]
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    [CrossRef]
  25. J. Hotta, K. Sasaki, and H. Masuhara, "Manipulation of liquid crystal textures with a focused near infrared beam," Appl. Phys. Lett. 71, 2085 (1997).
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  26. N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation of a smectic liquid-crystal droplet," Euro. Phys. J. E 20, 435 (2006).
    [CrossRef]
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    [CrossRef] [PubMed]
  28. N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
    [CrossRef]
  29. N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
    [CrossRef]
  30. A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
    [CrossRef]
  31. T. Tlusty, A. Meller, and R. Bar-Ziv, "Optical gradient forces of strongly localized fields," Phys. Rev. Lett. 81, 1738 (1998).
    [CrossRef]
  32. I. I. Smalyukh and O. D. Lavrentovich, Three-dimensional director structures of defects in Grandjean-Cano wedges of cholesteric liquid crystals studied by fluorescence confocal polarizing microscopy," Phys. Rev. E 66, 051703 (2002).
    [CrossRef]
  33. I. I. Smalyukh and O. D. Lavrentovich, "Anchoring-mediated interaction of edge dislocations with bounding surfaces in confined cholesteric liquid crystals," Phys. Rev. Lett. 90, 085503 (2003).
    [CrossRef] [PubMed]
  34. I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
    [CrossRef]
  35. I. I. Smalyukh, S. V. Shiyanovskii, and O. D. Lavrentovich,"Three-dimensional imaging of orientational order by fluorescence confocal polarizing microscopy," Chem. Phys. Lett. 336, 88 (2001).
    [CrossRef]
  36. I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
    [CrossRef] [PubMed]
  37. D. S. Kaputa, A. N. Kuzmin, A. V. Kachynski, A. N. Cartwright, P. N. Prasad, "Dynamics of multiple particle trapping by a single beam laser tweezer," Appl. Opt. 44, 3963 (2005).
    [CrossRef] [PubMed]
  38. B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system," Proc. R. Soc. London, Ser. A 253, 358 (1959).
    [CrossRef]
  39. A. Rohrbach, "Stiffness of optical traps: quantitative agreement between experiment and electromagnetic theory, "Phys. Rev. Lett. 95, 168102 (2005).
    [CrossRef] [PubMed]
  40. S. D. Durbin, S. M. Arakelian, and Y. R. Shen, "Optical-field-induced birefringence and Freedericksz transition in a nematic liquid crystal," Phys. Rev. Lett. 47, 1411 (1981).
    [CrossRef]
  41. E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
    [CrossRef] [PubMed]
  42. I.-C. Khoo, Liquid Crystals: Physical Properties and Nonlinear Optical Phenomena (Wiley, New York, 1995).
  43. I.-C. Khoo, P. Y. Yan, and T. H. Liu, "Nonlinear transverse dependence of optically induced director axis reorientation of a nematic liquid crystal film - theory and experiment," J. Opt. Soc. Am. B 4, 115 (1987).
    [CrossRef]
  44. E. J. G. Peterman, F. Gittes, and C. F. Schmidt, "Laser-induced heating in optical traps," Biophys. J. 84, 1308 (2003).
    [CrossRef] [PubMed]

2006

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
[CrossRef] [PubMed]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation of a smectic liquid-crystal droplet," Euro. Phys. J. E 20, 435 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation based on a light-induced molecular reordering," Opt. Express 14, 2481 (2006).
[CrossRef] [PubMed]

2005

D. S. Kaputa, A. N. Kuzmin, A. V. Kachynski, A. N. Cartwright, P. N. Prasad, "Dynamics of multiple particle trapping by a single beam laser tweezer," Appl. Opt. 44, 3963 (2005).
[CrossRef] [PubMed]

Y. Roichman and D. G. Grier, "Holographic assembly of quasicrystalline photonic heterostructures," Opt. Express 13, 5434 (2005).
[CrossRef] [PubMed]

N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
[CrossRef]

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
[CrossRef] [PubMed]

A. Rohrbach, "Stiffness of optical traps: quantitative agreement between experiment and electromagnetic theory, "Phys. Rev. Lett. 95, 168102 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

2004

T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
[CrossRef]

M. Yada, J. Yamamoto, and H. Yokoyama, "Direct observation of anisotropic interparticle forces in nematic colloids with optical tweezers," Phys. Rev. Lett. 92, 185501 (2004).
[CrossRef] [PubMed]

A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

K. C. Neuman and S. M. Block, "Optical trapping," Rev. Sci. Instrum. 75, 2787 (2004).
[CrossRef]

2003

D. G. Grier, "A revolution in optical manipulation," Nature 424, 810 (2003).
[CrossRef] [PubMed]

E. J. G. Peterman, F. Gittes, and C. F. Schmidt, "Laser-induced heating in optical traps," Biophys. J. 84, 1308 (2003).
[CrossRef] [PubMed]

I. I. Smalyukh and O. D. Lavrentovich, "Anchoring-mediated interaction of edge dislocations with bounding surfaces in confined cholesteric liquid crystals," Phys. Rev. Lett. 90, 085503 (2003).
[CrossRef] [PubMed]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
[CrossRef]

E. Hatta and Th. M. Fischer, "Splitting of an s = 1 point disclination into half-integer disclinations upon laser heating of a Langmuir monolayer," J. Phys. Chem. B 107, 6406 (2003).
[CrossRef]

2002

E. Hatta and Th. M. Fischer, "Liquid crystalline and solid stripe textures in Langmuir monolayers," Langmuir 18, 6201 (2002).
[CrossRef]

I. I. Smalyukh and O. D. Lavrentovich, Three-dimensional director structures of defects in Grandjean-Cano wedges of cholesteric liquid crystals studied by fluorescence confocal polarizing microscopy," Phys. Rev. E 66, 051703 (2002).
[CrossRef]

2001

I. I. Smalyukh, S. V. Shiyanovskii, and O. D. Lavrentovich,"Three-dimensional imaging of orientational order by fluorescence confocal polarizing microscopy," Chem. Phys. Lett. 336, 88 (2001).
[CrossRef]

P. Steffen, S. Wurlitzer, and Th. M. Fischer, "Hydrodynamics of shape relaxation in viscous Langmuir monolayer domains" J. Phys. Chem. A 105, 8281 (2001).
[CrossRef]

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

2000

S. Wurlitzer, P. Steffen and Th. M. Fischer, "Line tension of Langmuir monolayer phase boundaries determined with optical tweezers," J. Chem. Phys. 112, 5915 (2000).
[CrossRef]

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

1999

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

1998

T. Tlusty, A. Meller, and R. Bar-Ziv, "Optical gradient forces of strongly localized fields," Phys. Rev. Lett. 81, 1738 (1998).
[CrossRef]

1997

J. Hotta, K. Sasaki, and H. Masuhara, "Manipulation of liquid crystal textures with a focused near infrared beam," Appl. Phys. Lett. 71, 2085 (1997).
[CrossRef]

1987

I.-C. Khoo, P. Y. Yan, and T. H. Liu, "Nonlinear transverse dependence of optically induced director axis reorientation of a nematic liquid crystal film - theory and experiment," J. Opt. Soc. Am. B 4, 115 (1987).
[CrossRef]

E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
[CrossRef] [PubMed]

1986

1981

S. D. Durbin, S. M. Arakelian, and Y. R. Shen, "Optical-field-induced birefringence and Freedericksz transition in a nematic liquid crystal," Phys. Rev. Lett. 47, 1411 (1981).
[CrossRef]

1959

B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system," Proc. R. Soc. London, Ser. A 253, 358 (1959).
[CrossRef]

Abbate, G.

E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
[CrossRef] [PubMed]

Arakelian, S. M.

S. D. Durbin, S. M. Arakelian, and Y. R. Shen, "Optical-field-induced birefringence and Freedericksz transition in a nematic liquid crystal," Phys. Rev. Lett. 47, 1411 (1981).
[CrossRef]

Ashkin, A.

Babic, D.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Bar-Ziv, R.

T. Tlusty, A. Meller, and R. Bar-Ziv, "Optical gradient forces of strongly localized fields," Phys. Rev. Lett. 81, 1738 (1998).
[CrossRef]

Bjorkholm, J. E.

Block, S. M.

K. C. Neuman and S. M. Block, "Optical trapping," Rev. Sci. Instrum. 75, 2787 (2004).
[CrossRef]

Bodnar, V. H.

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Cartwright, A. N.

Chu, S.

Clark, N. A.

A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
[CrossRef]

Cristobal, G.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Dholakia, K.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Dickinson, M. R.

T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
[CrossRef]

Durbin, S. D.

S. D. Durbin, S. M. Arakelian, and Y. R. Shen, "Optical-field-induced birefringence and Freedericksz transition in a nematic liquid crystal," Phys. Rev. Lett. 47, 1411 (1981).
[CrossRef]

Duschl, C.

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

Dziedzic, J. M.

Fernández-Nieves, A.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Fischer, Th. M.

E. Hatta and Th. M. Fischer, "Splitting of an s = 1 point disclination into half-integer disclinations upon laser heating of a Langmuir monolayer," J. Phys. Chem. B 107, 6406 (2003).
[CrossRef]

E. Hatta and Th. M. Fischer, "Liquid crystalline and solid stripe textures in Langmuir monolayers," Langmuir 18, 6201 (2002).
[CrossRef]

P. Steffen, S. Wurlitzer, and Th. M. Fischer, "Hydrodynamics of shape relaxation in viscous Langmuir monolayer domains" J. Phys. Chem. A 105, 8281 (2001).
[CrossRef]

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

S. Wurlitzer, P. Steffen and Th. M. Fischer, "Line tension of Langmuir monolayer phase boundaries determined with optical tweezers," J. Chem. Phys. 112, 5915 (2000).
[CrossRef]

Garcés-Chávez, V.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Gartland, E. C.

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Gittes, F.

E. J. G. Peterman, F. Gittes, and C. F. Schmidt, "Laser-induced heating in optical traps," Biophys. J. 84, 1308 (2003).
[CrossRef] [PubMed]

Gleeson, H. F.

T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
[CrossRef]

Grier, D. G.

Hasegawa, I.

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
[CrossRef]

Hatta, E.

E. Hatta and Th. M. Fischer, "Splitting of an s = 1 point disclination into half-integer disclinations upon laser heating of a Langmuir monolayer," J. Phys. Chem. B 107, 6406 (2003).
[CrossRef]

E. Hatta and Th. M. Fischer, "Liquid crystalline and solid stripe textures in Langmuir monolayers," Langmuir 18, 6201 (2002).
[CrossRef]

Hotta, J.

J. Hotta, K. Sasaki, and H. Masuhara, "Manipulation of liquid crystal textures with a focused near infrared beam," Appl. Phys. Lett. 71, 2085 (1997).
[CrossRef]

Huang, H.

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Jarutis, V.

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

Juodkazis, S.

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation of a smectic liquid-crystal droplet," Euro. Phys. J. E 20, 435 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation based on a light-induced molecular reordering," Opt. Express 14, 2481 (2006).
[CrossRef] [PubMed]

N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

Kachynski, A.

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

Kachynski, A. V.

I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
[CrossRef] [PubMed]

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

D. S. Kaputa, A. N. Kuzmin, A. V. Kachynski, A. N. Cartwright, P. N. Prasad, "Dynamics of multiple particle trapping by a single beam laser tweezer," Appl. Opt. 44, 3963 (2005).
[CrossRef] [PubMed]

Kaputa, D. S.

Khattari, Z.

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

Khoo, I.-C.

Kosa, T.

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Kuzmin, A.

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

Kuzmin, A. N.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
[CrossRef] [PubMed]

D. S. Kaputa, A. N. Kuzmin, A. V. Kachynski, A. N. Cartwright, P. N. Prasad, "Dynamics of multiple particle trapping by a single beam laser tweezer," Appl. Opt. 44, 3963 (2005).
[CrossRef] [PubMed]

Lautz, C.

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

Lavrentovich, O. D.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh and O. D. Lavrentovich, "Anchoring-mediated interaction of edge dislocations with bounding surfaces in confined cholesteric liquid crystals," Phys. Rev. Lett. 90, 085503 (2003).
[CrossRef] [PubMed]

I. I. Smalyukh and O. D. Lavrentovich, Three-dimensional director structures of defects in Grandjean-Cano wedges of cholesteric liquid crystals studied by fluorescence confocal polarizing microscopy," Phys. Rev. E 66, 051703 (2002).
[CrossRef]

I. I. Smalyukh, S. V. Shiyanovskii, and O. D. Lavrentovich,"Three-dimensional imaging of orientational order by fluorescence confocal polarizing microscopy," Chem. Phys. Lett. 336, 88 (2001).
[CrossRef]

Liley, M.

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

Liu, T. H.

Maclennan, J. E.

A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
[CrossRef]

Maddalena, P.

E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
[CrossRef] [PubMed]

Madhusudana, N. V.

I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
[CrossRef] [PubMed]

Masuhara, H.

J. Hotta, K. Sasaki, and H. Masuhara, "Manipulation of liquid crystal textures with a focused near infrared beam," Appl. Phys. Lett. 71, 2085 (1997).
[CrossRef]

Matsuo, S.

N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

Meller, A.

T. Tlusty, A. Meller, and R. Bar-Ziv, "Optical gradient forces of strongly localized fields," Phys. Rev. Lett. 81, 1738 (1998).
[CrossRef]

Misawa, H.

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation of a smectic liquid-crystal droplet," Euro. Phys. J. E 20, 435 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation based on a light-induced molecular reordering," Opt. Express 14, 2481 (2006).
[CrossRef] [PubMed]

N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

Murazawa, N.

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation of a smectic liquid-crystal droplet," Euro. Phys. J. E 20, 435 (2006).
[CrossRef]

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation based on a light-induced molecular reordering," Opt. Express 14, 2481 (2006).
[CrossRef] [PubMed]

N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
[CrossRef]

Muševic, I.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Nazarenko, V.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Neuman, K. C.

K. C. Neuman and S. M. Block, "Optical trapping," Rev. Sci. Instrum. 75, 2787 (2004).
[CrossRef]

Nych, A.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Ognysta, U.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

Osterman, N.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Palffy-Muhoray, P.

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Park, C. S.

A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
[CrossRef]

Pattanaporkratana, A.

A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
[CrossRef]

Peterman, E. J. G.

E. J. G. Peterman, F. Gittes, and C. F. Schmidt, "Laser-induced heating in optical traps," Biophys. J. 84, 1308 (2003).
[CrossRef] [PubMed]

Poberaj, I.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Prasad, P. N.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
[CrossRef] [PubMed]

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

D. S. Kaputa, A. N. Kuzmin, A. V. Kachynski, A. N. Cartwright, P. N. Prasad, "Dynamics of multiple particle trapping by a single beam laser tweezer," Appl. Opt. 44, 3963 (2005).
[CrossRef] [PubMed]

Pratibha, R.

I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
[CrossRef] [PubMed]

Ravnik, M.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

Richards, B.

B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system," Proc. R. Soc. London, Ser. A 253, 358 (1959).
[CrossRef]

Rohrbach, A.

A. Rohrbach, "Stiffness of optical traps: quantitative agreement between experiment and electromagnetic theory, "Phys. Rev. Lett. 95, 168102 (2005).
[CrossRef] [PubMed]

Roichman, Y.

Santamato, E.

E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
[CrossRef] [PubMed]

Sasaki, K.

J. Hotta, K. Sasaki, and H. Masuhara, "Manipulation of liquid crystal textures with a focused near infrared beam," Appl. Phys. Lett. 71, 2085 (1997).
[CrossRef]

Schmidt, C. F.

E. J. G. Peterman, F. Gittes, and C. F. Schmidt, "Laser-induced heating in optical traps," Biophys. J. 84, 1308 (2003).
[CrossRef] [PubMed]

Senyuk, B. I.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Shen, Y. R.

E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
[CrossRef] [PubMed]

S. D. Durbin, S. M. Arakelian, and Y. R. Shen, "Optical-field-induced birefringence and Freedericksz transition in a nematic liquid crystal," Phys. Rev. Lett. 47, 1411 (1981).
[CrossRef]

Shikata, M.

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

Shiyanovskii, S. V.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, S. V. Shiyanovskii, and O. D. Lavrentovich,"Three-dimensional imaging of orientational order by fluorescence confocal polarizing microscopy," Chem. Phys. Lett. 336, 88 (2001).
[CrossRef]

Škarabot, M.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

Smalyukh, I. I.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
[CrossRef] [PubMed]

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
[CrossRef] [PubMed]

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

I. I. Smalyukh and O. D. Lavrentovich, "Anchoring-mediated interaction of edge dislocations with bounding surfaces in confined cholesteric liquid crystals," Phys. Rev. Lett. 90, 085503 (2003).
[CrossRef] [PubMed]

I. I. Smalyukh and O. D. Lavrentovich, Three-dimensional director structures of defects in Grandjean-Cano wedges of cholesteric liquid crystals studied by fluorescence confocal polarizing microscopy," Phys. Rev. E 66, 051703 (2002).
[CrossRef]

I. I. Smalyukh, S. V. Shiyanovskii, and O. D. Lavrentovich,"Three-dimensional imaging of orientational order by fluorescence confocal polarizing microscopy," Chem. Phys. Lett. 336, 88 (2001).
[CrossRef]

Spalding, G. C.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Steffen, P.

P. Steffen, S. Wurlitzer, and Th. M. Fischer, "Hydrodynamics of shape relaxation in viscous Langmuir monolayer domains" J. Phys. Chem. A 105, 8281 (2001).
[CrossRef]

S. Wurlitzer, P. Steffen and Th. M. Fischer, "Line tension of Langmuir monolayer phase boundaries determined with optical tweezers," J. Chem. Phys. 112, 5915 (2000).
[CrossRef]

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

Taheri, B.

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

Takahashi, T.

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

Tanamura, Y.

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

Tlusty, T.

T. Tlusty, A. Meller, and R. Bar-Ziv, "Optical gradient forces of strongly localized fields," Phys. Rev. Lett. 81, 1738 (1998).
[CrossRef]

Weitz, D. A.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Wolf, E.

B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system," Proc. R. Soc. London, Ser. A 253, 358 (1959).
[CrossRef]

Wood, T. A.

T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
[CrossRef]

Wright, A. J.

T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
[CrossRef]

Wurlitzer, M.

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

Wurlitzer, S.

P. Steffen, S. Wurlitzer, and Th. M. Fischer, "Hydrodynamics of shape relaxation in viscous Langmuir monolayer domains" J. Phys. Chem. A 105, 8281 (2001).
[CrossRef]

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

S. Wurlitzer, P. Steffen and Th. M. Fischer, "Line tension of Langmuir monolayer phase boundaries determined with optical tweezers," J. Chem. Phys. 112, 5915 (2000).
[CrossRef]

Yada, M.

M. Yada, J. Yamamoto, and H. Yokoyama, "Direct observation of anisotropic interparticle forces in nematic colloids with optical tweezers," Phys. Rev. Lett. 92, 185501 (2004).
[CrossRef] [PubMed]

Yamamoto, J.

M. Yada, J. Yamamoto, and H. Yokoyama, "Direct observation of anisotropic interparticle forces in nematic colloids with optical tweezers," Phys. Rev. Lett. 92, 185501 (2004).
[CrossRef] [PubMed]

Yan, P. Y.

Yokoyama, H.

M. Yada, J. Yamamoto, and H. Yokoyama, "Direct observation of anisotropic interparticle forces in nematic colloids with optical tweezers," Phys. Rev. Lett. 92, 185501 (2004).
[CrossRef] [PubMed]

Žumer, S.

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

Adv. Mater.

A. Fernández-Nieves, G. Cristobal, V. Garcés-Chávez, G. C. Spalding, K. Dholakia, and D. A. Weitz, "Optically anisotropic colloids of controllable shape," Adv. Mater. 17, 680 (2005).
[CrossRef]

Appl. Opt.

Appl. Phys. Lett.

J. Hotta, K. Sasaki, and H. Masuhara, "Manipulation of liquid crystal textures with a focused near infrared beam," Appl. Phys. Lett. 71, 2085 (1997).
[CrossRef]

T. A. Wood, H. F. Gleeson, M. R. Dickinson, and A. J. Wright, "Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets," Appl. Phys. Lett. 84, 4292 (2004).
[CrossRef]

I. I. Smalyukh, A. Kuzmin, A. Kachynski, P. N. Prasad, and O. D. Lavrentovich, "Optical trapping of colloidal particles and measurement of the defect line tension and colloidal forces in a thermotropic nematic liquid crystal," Appl. Phys. Lett. 86, 021913 (2005).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, "Fast optical switching by a laser-manipulated micro-droplet of liquid crystal," Appl. Phys. Lett. 74, 3627 (1999).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, "High-efficiency optical transfer of torque to a nematic liquid crystal droplet," Appl. Phys. Lett. 82, 4657 (2003).
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Biophys. J.

E. J. G. Peterman, F. Gittes, and C. F. Schmidt, "Laser-induced heating in optical traps," Biophys. J. 84, 1308 (2003).
[CrossRef] [PubMed]

Chem. Phys. Lett.

I. I. Smalyukh, S. V. Shiyanovskii, and O. D. Lavrentovich,"Three-dimensional imaging of orientational order by fluorescence confocal polarizing microscopy," Chem. Phys. Lett. 336, 88 (2001).
[CrossRef]

Eur. Phys. J. E

I. I. Smalyukh, R. Pratibha, N. V. Madhusudana, and O. D. Lavrentovich, "Selective imaging of 3-D director fields and study of defects in biaxial smectic A liquid crystals," Eur. Phys. J. E 16, 179 (2005).
[CrossRef] [PubMed]

Euro. Phys. J. E

N. Murazawa, S. Juodkazis, and H. Misawa, "Laser manipulation of a smectic liquid-crystal droplet," Euro. Phys. J. E 20, 435 (2006).
[CrossRef]

Europhys. Lett.

N. Murazawa, S. Juodkazis, V. Jarutis, Y. Tanamura, and H. Misawa, "Viscosity measurement using a rotating laser-trapped microsphere of liquid crystal," Europhys. Lett. 73, 800 (2006).
[CrossRef]

Ferroelectrics

A. Pattanaporkratana, C. S. Park, J. E. Maclennan, and N. A. Clark, "Manipulation of disk-shaped islands on freely suspended smectic films and CDs using optical tweezers," Ferroelectrics 310, 131 (2004).
[CrossRef]

J. Chem. Phys.

S. Wurlitzer, P. Steffen and Th. M. Fischer, "Line tension of Langmuir monolayer phase boundaries determined with optical tweezers," J. Chem. Phys. 112, 5915 (2000).
[CrossRef]

S. Wurlitzer, P. Steffen, M. Wurlitzer, Z. Khattari, and Th. M. Fischer, "Line tension in Langmuir monolayers probed by point forces" J. Chem. Phys. 113, 3822 (2000).
[CrossRef]

J. Opt. Soc. Am. B

J. Phys. Chem. A

P. Steffen, S. Wurlitzer, and Th. M. Fischer, "Hydrodynamics of shape relaxation in viscous Langmuir monolayer domains" J. Phys. Chem. A 105, 8281 (2001).
[CrossRef]

J. Phys. Chem. B

S. Wurlitzer, C. Lautz, M. Liley, C. Duschl, and Th. M. Fischer, "Micromanipulation of Langmuir monolayers with optical tweezers" J. Phys. Chem. B 105, 182 (2001).
[CrossRef]

E. Hatta and Th. M. Fischer, "Splitting of an s = 1 point disclination into half-integer disclinations upon laser heating of a Langmuir monolayer," J. Phys. Chem. B 107, 6406 (2003).
[CrossRef]

Langmuir

E. Hatta and Th. M. Fischer, "Liquid crystalline and solid stripe textures in Langmuir monolayers," Langmuir 18, 6201 (2002).
[CrossRef]

Mol. Cryst. Liq. Cryst.

I. I. Smalyukh, B. I. Senyuk, S. V. Shiyanovskii, O. D. Lavrentovich, A. N. Kuzmin, A. V. Kachynski, and P. N. Prasad, "Optical trapping, manipulation, and 3-D Imaging of disclinations in liquid crystals and measurement of their line tension," Mol. Cryst. Liq. Cryst. 450, 79 (2006).
[CrossRef]

Nature

D. G. Grier, "A revolution in optical manipulation," Nature 424, 810 (2003).
[CrossRef] [PubMed]

Opt. Express

Opt. Lett.

Phys. Rev. A

E. Santamato, G. Abbate, P. Maddalena, and Y. R. Shen, "Optically induced twist Freedericksz transition in planar-aligned nematic liquid crystals," Phys. Rev. A 36, 2389 (1987).
[CrossRef] [PubMed]

Phys. Rev. E

I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, and B. Taheri, "Electric-field-induced nematic-cholesteric transition and three-dimensional director structures in homeotropic cells," Phys. Rev. E 72, 061707 (2005).
[CrossRef]

I. I. Smalyukh and O. D. Lavrentovich, Three-dimensional director structures of defects in Grandjean-Cano wedges of cholesteric liquid crystals studied by fluorescence confocal polarizing microscopy," Phys. Rev. E 66, 051703 (2002).
[CrossRef]

M. Škarabot, M. Ravnik, D. Babič, N. Osterman, I. Poberaj, S. Žumer, I. Muševič, A. Nych, U. Ognysta, and V. Nazarenko, "Laser trapping of low refractive index colloids in a nematic liquid crystal," Phys. Rev. E 73, 021705 (2006).
[CrossRef]

Phys. Rev. Lett.

I. Muševič, M. Škarabot, D. Babič, N. Osterman, I. Poberaj, V. Nazarenko, A. Nych, "Laser trapping of small colloidal particles in a nematic liquid crystal: clouds and ghosts," Phys. Rev. Lett. 93, 187801 (2004).
[CrossRef] [PubMed]

I. I. Smalyukh, O. D. Lavrentovich, A. Kuzmin, A. Kachynski, and P. N. Prasad, "Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal," Phys. Rev. Lett. 95, 157801 (2005).
[CrossRef] [PubMed]

M. Yada, J. Yamamoto, and H. Yokoyama, "Direct observation of anisotropic interparticle forces in nematic colloids with optical tweezers," Phys. Rev. Lett. 92, 185501 (2004).
[CrossRef] [PubMed]

I. I. Smalyukh and O. D. Lavrentovich, "Anchoring-mediated interaction of edge dislocations with bounding surfaces in confined cholesteric liquid crystals," Phys. Rev. Lett. 90, 085503 (2003).
[CrossRef] [PubMed]

T. Tlusty, A. Meller, and R. Bar-Ziv, "Optical gradient forces of strongly localized fields," Phys. Rev. Lett. 81, 1738 (1998).
[CrossRef]

A. Rohrbach, "Stiffness of optical traps: quantitative agreement between experiment and electromagnetic theory, "Phys. Rev. Lett. 95, 168102 (2005).
[CrossRef] [PubMed]

S. D. Durbin, S. M. Arakelian, and Y. R. Shen, "Optical-field-induced birefringence and Freedericksz transition in a nematic liquid crystal," Phys. Rev. Lett. 47, 1411 (1981).
[CrossRef]

Proc. Natl. Acad. Sci. U.S.A.

I. I. Smalyukh, A. V. Kachynski, A. N. Kuzmin, and P. N. Prasad, "Laser trapping in anisotropic fluids and polarization controlled particle dynamics," Proc. Natl. Acad. Sci. U.S.A. 103, 18048 (2006).
[CrossRef] [PubMed]

Proc. R. Soc. London, Ser. A

B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system," Proc. R. Soc. London, Ser. A 253, 358 (1959).
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K. C. Neuman and S. M. Block, "Optical trapping," Rev. Sci. Instrum. 75, 2787 (2004).
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N. Murazawa, S. Juodkazis, S. Matsuo, and H. Misawa, "Control of the molecular alignment inside liquid-crystal droplets by use of laser tweezers," Small 1, 656 (2005).
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Supplementary Material (3)

» Media 1: AVI (2069 KB)     
» Media 2: AVI (1116 KB)     
» Media 3: AVI (1897 KB)     

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Figures (7)

Figs. 1.
Figs. 1.

(a). − 1(c). Polarizing microscopy textures: (a) domains with a uniform (left) and the 180° -twisted across a cell director (right); (b) cholesteric fingers in a homeotropic cell; (c) toric focal conic domains in a smectic LC. (d-f) Director fields in vertical cross-sections of the structures: (d) for a wedge cell shown in (a) with a disclination line separating the two domains; (e) for a cholesteric finger of the CF3 type; (f) for the toric focal conic domain. The defect lines in (d-f) are marked by the red lines or filled circles. Note that four different types of cholesteric fingers are known [34], and (e) illustrates the simplest one. Crossed polarizers in (a-c) are along the vertical and horizontal image edges.

Fig. 2.
Fig. 2.

Optical manipulation of cholesteric CDs: (a, 2 MB) video sequence and [Media 1] (b-e) extracted images. Using a single beam that is time-shared between four traps, four CDs (marked by white arrows in (a)) are first positioned in vertices of a square and then are set to follow computer-programmed concentric motion trajectories as shown in video frames (a-e) taken at about 1s time intervals. (f) The director structure of the CD in the plane of the LC cell. Textures (a-e) were obtained with the crossed polarizer and analyzer along the image edges. The black ellipses in (f) mark the two equally-possible trapping cites for large CDs when the trap’s linear polarization is along the horizontal direction (marked by the black bar and “P”).

Fig. 3.
Fig. 3.

Stretching of an optically trapped dislocation in a lamellar LC by moving the sample using a stage: (a, 1.1 MB) video sequence and [Media 2] (b-g) extracted representative image frames. The directions of the sample displacement are shown by the black arrows in (a-g). (h) Layers profile in the vertical FCPM cross-section that was obtained (before the optical trapping experiments) in the plane orthogonal to the dislocation, as shown by the h-h line in (d). Schematics of the director field around the defect core shown by the red circle in (h). Linear polarization direction of the trapping laser beam is along the y-axis in (a-g). FCPM polarization direction in (h) is along the defect line. Polarizing microscopy textures (a-g) were obtained with the crossed polarizer and analyzer along the vertical/horizontal image edges.

Fig. 4.
Fig. 4.

Laser manipulation of a disclination quadrupole: (a, 1.9 MB) video sequence and [Media 3] (b-f) extracted frames. A single beam is time-shared between the two IR traps visualized in (a) by a HeNe laser beam co-localized with the trapping beam. The traps are slowly shifted as shown by white arrows in (a) and the disclinations are stretched (a-f) until they escape from the traps (f), because of their line tension. (g) Layers structure visualized by the FCPM for the vertical cross-section perpendicular to the cluster, as marked by the g-g line in (b). (h) The director field around the disclination cluster shown by the red circle in (g). Linear polarization of the laser beam used for manipulation is along the y-axis in (a-f). FCPM polarization direction is normal to the image and along the cluster in (g). Textures (a-f) were obtained with the crossed polarizer and analyzer along the image edges.

Fig. 5.
Fig. 5.

(a). An image showing that a linearly-polarized beam of powerW ≈ 100mW exerts torsion and locally reorients an initially straight disclination cluster shown in Figs. 4. (b), 4(c) Schematics of the molecular alignment in the central part of (b) the undistorted cluster [similar to that shown in Fig. 4(h)] and (c) with the local laser-induced director reorientation that results in the structure trapping at high powers, as shown in (a). Crossed polarizers are along the image edges in (a).

Fig. 6.
Fig. 6.

Models of the LC structures and the calculated optical gradient forces. (a) A semi-infinite domain (SID) of thickness lz extending from x=0 (thick lines in (a)) to infinity ∞ along the x-axis and from −∞to ∞ along the y-axis.(b) A stripe-like domain (SD) of thickness lz width lx and extending from −∞ to ∞ along the y-axis. (c) A domain with finite dimensions. (d-f) Calculated gradient forces vs. the distance to the trap’s center: (d) for the structures shown in (a) using Eq.(6); (e) for the SD fragment using Eq.(4) and sizes marked on the figure; (f) for the structure shown in (c) using Eq.(2) and the marked sizes l = lx =ly =lz . We used W = 15mW and indices marked in (d) in calculations for the SID. Indices nDS = 1.55,nSLC = 1.47 were used in the calculations for the SD and the cubic domain in (e,f).

Fig. 7.
Fig. 7.

Optical gradient forces calculated for the cholesteric CD and for power W = 15mW . The values of pitch p are marked for each curve. The trapping positions (zero force) are shown by the arrows. Note that large CDs can be trapped at a finite distance from their center.

Equations (7)

Equations on this page are rendered with MathJax. Learn more.

f ( r ) = ε 0 2 [ n SLC 2 n DS 2 ] V DS E ( r , z ) 2 dV ,
F cubic ( r ) = A cubic exp [ r ( l + r ) 2 ω 2 ] [ exp ( lr ω 2 ) 1 ] ,
A cubic = 2 gξW ( n DS 2 / n SLC 2 1 ) c erf ( l 2 2 ω ) erf ( l 2 2 ωξ ) exp ( l 2 8 ω 2 ) ,
F x / y SD ( r ) = A x / y SD exp [ r ( r + l x / y ) 2 ω 2 ] [ exp ( rl x / y ω 2 ) 1 ] ,
A x / y SD = 2gξW ( n DS 2 / n SLC 2 1 ) c erf [ l x / y 2 2 ω ] erf [ l z 2 2 ωξ ] exp [ l x / y 2 8 ω 2 ] .
F x SID ( r ) = 2 g ξ W ( n DS 2 / n SLC 2 1 ) c exp ( r 2 2 ω 2 ) ; F y SID = 0.
f elastic ( r ) = 1 2 [ K 1 ( N ̂ ( r ) ) 2 + K 2 ( N ̂ ( r ) ( × N ̂ ( r ) ) ) 2 + K 3 ( N ̂ ( r ) × ( × N ̂ ( r ) ) ) 2 ] dV ,

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