Abstract

We present the first observation, to our knowledge, of lasing from a levitated, dye droplet. The levitated droplets are created by computer controlled pico-liter dispensing into one of the nodes of a standing ultrasonic wave (100 kHz), where the droplet is trapped. The free hanging droplet forms a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating spectrometer. With this setup we have achieved reproducible lasing spectra in the visible wavelength range from 610 nm to 650 nm. The levitated droplet technique has previously successfully been applied for a variety of bio-analytical applications at single cell level. In combination with the lasing droplets, the capability of this high precision setup has potential applications within highly sensitive intra-cavity absorbance detection.

© 2006 Optical Society of America

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  1. K. J. Vahala, "Optical microcavities," Nature 424, 839 - 846 (2003).
    [CrossRef] [PubMed]
  2. S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
    [CrossRef] [PubMed]
  3. A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
    [CrossRef] [PubMed]
  4. J. U. Nockel and A. D. Stone, "Ray and wave chaos in asymmetric resonant optical cavities," Nature 385, 45 -47 (1997).
    [CrossRef]
  5. E. G. Lierke, "Acoustic levitation - A comprehensive survey of principles and applications," Acustica 82, 220 -237 (1996).
  6. S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
    [CrossRef] [PubMed]
  7. S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
    [CrossRef] [PubMed]
  8. R. Symes, R. M. Sayer, and J. P. Reid, "Cavity enhanced droplet spectroscopy: Principles, perspectives and prospects," Phys. Chem. Chem. Phys. 6, 474 - 487 (2004).
    [CrossRef]
  9. V. V. Datsyuk, "Optics of microdroplets," J. Mol. Liq. 93, 159 - 175 (2001).
    [CrossRef]
  10. S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
    [CrossRef] [PubMed]
  11. S. Santesson and S. Nilsson, "Airborne chemistry: acoustic levitation in chemical analysis," Anal. Bioanal. Chem. 378, 1704 - 1709 (2004).
    [CrossRef] [PubMed]
  12. Tech5 AG, URL http://www.tec5.com.
  13. H. Fiehn, S. Howitz, and T. Wegener, "New technology for the precision dosage of liquids in the range of microlitres and submicrolitres," Pharm. Ind. 59, 814 - 817 (1997).
  14. L. D. Landau and E. M. Lifshitz, Fluid Mechanics, vol. 6 of Course of Theoretical Physics, 2nd ed. (Butterworth Heinemann, Oxford, 1987).
  15. A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
    [CrossRef]
  16. J. R. Buck and H. J. Kimble, "Optimal sizes of dielectric microspheres for cavity QED with strong coupling," Phys. Rev. A 67, 033,806 (2003).
    [CrossRef]
  17. M. L. Gorodetsky, A. A. Savchenkov, and V. S. Ilchenko, "Ultimate Q of optical microsphere resonators," Opt. Lett. 21, 453 - 455 (1996).
    [CrossRef] [PubMed]

2004 (2)

R. Symes, R. M. Sayer, and J. P. Reid, "Cavity enhanced droplet spectroscopy: Principles, perspectives and prospects," Phys. Chem. Chem. Phys. 6, 474 - 487 (2004).
[CrossRef]

S. Santesson and S. Nilsson, "Airborne chemistry: acoustic levitation in chemical analysis," Anal. Bioanal. Chem. 378, 1704 - 1709 (2004).
[CrossRef] [PubMed]

2003 (4)

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

J. R. Buck and H. J. Kimble, "Optimal sizes of dielectric microspheres for cavity QED with strong coupling," Phys. Rev. A 67, 033,806 (2003).
[CrossRef]

K. J. Vahala, "Optical microcavities," Nature 424, 839 - 846 (2003).
[CrossRef] [PubMed]

2002 (1)

A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
[CrossRef]

2001 (1)

V. V. Datsyuk, "Optics of microdroplets," J. Mol. Liq. 93, 159 - 175 (2001).
[CrossRef]

2000 (1)

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

1997 (2)

J. U. Nockel and A. D. Stone, "Ray and wave chaos in asymmetric resonant optical cavities," Nature 385, 45 -47 (1997).
[CrossRef]

H. Fiehn, S. Howitz, and T. Wegener, "New technology for the precision dosage of liquids in the range of microlitres and submicrolitres," Pharm. Ind. 59, 814 - 817 (1997).

1996 (2)

M. L. Gorodetsky, A. A. Savchenkov, and V. S. Ilchenko, "Ultimate Q of optical microsphere resonators," Opt. Lett. 21, 453 - 455 (1996).
[CrossRef] [PubMed]

E. G. Lierke, "Acoustic levitation - A comprehensive survey of principles and applications," Acustica 82, 220 -237 (1996).

1995 (1)

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

1986 (1)

S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
[CrossRef] [PubMed]

Andersson, M.

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

Brenn, G.

A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
[CrossRef]

Buck, J. R.

J. R. Buck and H. J. Kimble, "Optimal sizes of dielectric microspheres for cavity QED with strong coupling," Phys. Rev. A 67, 033,806 (2003).
[CrossRef]

Cedergren-Zeppezauer, E. S.

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

Chang, R. K.

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
[CrossRef] [PubMed]

Chen, G.

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

Datsyuk, V. V.

V. V. Datsyuk, "Optics of microdroplets," J. Mol. Liq. 93, 159 - 175 (2001).
[CrossRef]

Degerman, E.

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

Fiehn, H.

H. Fiehn, S. Howitz, and T. Wegener, "New technology for the precision dosage of liquids in the range of microlitres and submicrolitres," Pharm. Ind. 59, 814 - 817 (1997).

Fox, S.

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

Gorodetsky, M. L.

Howitz, S.

H. Fiehn, S. Howitz, and T. Wegener, "New technology for the precision dosage of liquids in the range of microlitres and submicrolitres," Pharm. Ind. 59, 814 - 817 (1997).

Ilchenko, V. S.

Johansson, J.

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

Johansson, T.

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

Kimble, H. J.

J. R. Buck and H. J. Kimble, "Optimal sizes of dielectric microspheres for cavity QED with strong coupling," Phys. Rev. A 67, 033,806 (2003).
[CrossRef]

Laurell, T.

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

Levander, I.

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

Lierke, E. G.

E. G. Lierke, "Acoustic levitation - A comprehensive survey of principles and applications," Acustica 82, 220 -237 (1996).

Mekis, A.

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

Nilsson, J.

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

Nilsson, S.

S. Santesson and S. Nilsson, "Airborne chemistry: acoustic levitation in chemical analysis," Anal. Bioanal. Chem. 378, 1704 - 1709 (2004).
[CrossRef] [PubMed]

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

Nockel, J. U.

J. U. Nockel and A. D. Stone, "Ray and wave chaos in asymmetric resonant optical cavities," Nature 385, 45 -47 (1997).
[CrossRef]

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

Qian, S. X.

S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
[CrossRef] [PubMed]

Reid, J. P.

R. Symes, R. M. Sayer, and J. P. Reid, "Cavity enhanced droplet spectroscopy: Principles, perspectives and prospects," Phys. Chem. Chem. Phys. 6, 474 - 487 (2004).
[CrossRef]

Rensink, D.

A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
[CrossRef]

Santesson, S.

S. Santesson and S. Nilsson, "Airborne chemistry: acoustic levitation in chemical analysis," Anal. Bioanal. Chem. 378, 1704 - 1709 (2004).
[CrossRef] [PubMed]

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

Savchenkov, A. A.

Sayer, R. M.

R. Symes, R. M. Sayer, and J. P. Reid, "Cavity enhanced droplet spectroscopy: Principles, perspectives and prospects," Phys. Chem. Chem. Phys. 6, 474 - 487 (2004).
[CrossRef]

Sepaniak, M.

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

Snow, J. B.

S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
[CrossRef] [PubMed]

Stone, A. D.

J. U. Nockel and A. D. Stone, "Ray and wave chaos in asymmetric resonant optical cavities," Nature 385, 45 -47 (1997).
[CrossRef]

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

Symes, R.

R. Symes, R. M. Sayer, and J. P. Reid, "Cavity enhanced droplet spectroscopy: Principles, perspectives and prospects," Phys. Chem. Chem. Phys. 6, 474 - 487 (2004).
[CrossRef]

Taylor, L. S.

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

Tzeng, H. M.

S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
[CrossRef] [PubMed]

Vahala, K. J.

K. J. Vahala, "Optical microcavities," Nature 424, 839 - 846 (2003).
[CrossRef] [PubMed]

Wegener, T.

H. Fiehn, S. Howitz, and T. Wegener, "New technology for the precision dosage of liquids in the range of microlitres and submicrolitres," Pharm. Ind. 59, 814 - 817 (1997).

Weiss, D. A.

A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
[CrossRef]

Yarin, A. L.

A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
[CrossRef]

Acustica (1)

E. G. Lierke, "Acoustic levitation - A comprehensive survey of principles and applications," Acustica 82, 220 -237 (1996).

Anal. Bioanal. Chem. (1)

S. Santesson and S. Nilsson, "Airborne chemistry: acoustic levitation in chemical analysis," Anal. Bioanal. Chem. 378, 1704 - 1709 (2004).
[CrossRef] [PubMed]

Anal. Chem. (3)

S. Santesson, E. S. Cedergren-Zeppezauer, T. Johansson, T. Laurell, J. Nilsson, and S. Nilsson, "Screening of nucleation conditions using levitated drops for protein crystallization," Anal. Chem. 75, 1733 - 1740 (2003).
[CrossRef] [PubMed]

S. Santesson, M. Andersson, E. Degerman, T. Johansson, J. Nilsson, and S. Nilsson, "Airborne cell analysis," Anal. Chem. 72, 3412 - 3418 (2000).
[CrossRef] [PubMed]

S. Santesson, J. Johansson, L. S. Taylor, I. Levander, S. Fox, M. Sepaniak, and S. Nilsson, "Airborne chemistry coupled to Raman spectroscopy," Anal. Chem. 75, 2177 - 2180 (2003).
[CrossRef] [PubMed]

Int. J. Multiph. Flow (1)

A. L. Yarin, D. A. Weiss, G. Brenn, and D. Rensink, "Acoustically levitated drops: drop oscillation and break-up driven by ultrasound modulation," Int. J. Multiph. Flow 28, 887-910 (2002).
[CrossRef]

J. Mol. Liq. (1)

V. V. Datsyuk, "Optics of microdroplets," J. Mol. Liq. 93, 159 - 175 (2001).
[CrossRef]

Nature (2)

K. J. Vahala, "Optical microcavities," Nature 424, 839 - 846 (2003).
[CrossRef] [PubMed]

J. U. Nockel and A. D. Stone, "Ray and wave chaos in asymmetric resonant optical cavities," Nature 385, 45 -47 (1997).
[CrossRef]

Opt. Lett. (1)

Pharm. Ind. (1)

H. Fiehn, S. Howitz, and T. Wegener, "New technology for the precision dosage of liquids in the range of microlitres and submicrolitres," Pharm. Ind. 59, 814 - 817 (1997).

Phys. Chem. Chem. Phys. (1)

R. Symes, R. M. Sayer, and J. P. Reid, "Cavity enhanced droplet spectroscopy: Principles, perspectives and prospects," Phys. Chem. Chem. Phys. 6, 474 - 487 (2004).
[CrossRef]

Phys. Rev. A (1)

J. R. Buck and H. J. Kimble, "Optimal sizes of dielectric microspheres for cavity QED with strong coupling," Phys. Rev. A 67, 033,806 (2003).
[CrossRef]

Phys. Rev. Lett. (1)

A. Mekis, J. U. Nockel, G. Chen, A. D. Stone, and R. K. Chang, "Ray chaos and Q spoiling in lasing droplets," Phys. Rev. Lett. 75, 2682 - 2685 (1995).
[CrossRef] [PubMed]

Science (1)

S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, "Lasing droplets - highlighting the liquid-air interface by laser-emission," Science 231, 486 - 488 (1986).
[CrossRef] [PubMed]

Other (2)

L. D. Landau and E. M. Lifshitz, Fluid Mechanics, vol. 6 of Course of Theoretical Physics, 2nd ed. (Butterworth Heinemann, Oxford, 1987).

Tech5 AG, URL http://www.tec5.com.

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Figures (3)

Fig. 1.
Fig. 1.

a) Photograph of a lasing levitated micro-droplet. b) Schematics of ultrasonic field with the micro-droplet being trapped at a node in the ultrasonic field. c) Schematics of whispering-gallery modes in a (2D) spherical cavity. d) Numerical example of a whispering-gallery mode in a (2D) spherical cavity.

Fig. 2.
Fig. 2.

Reproducible lasing spectra from dye doped micro-droplets. Each spectrum is obtained in a fixed setup by a well-controlled loading of an EG droplet with a Rh6G dye which is subsequently pumped above threshold, see Fig. 3(b). The spectra are averaged over three pump pulses.

Fig. 3.
Fig. 3.

a) Cavity output power for increasing and decreasing average pump power. Each spectrum is obtained in a fixed setup by pumping an EG droplet with a Rh6G dye. The pump power is first increased from zero up to level around 1000mW (dashed curves) and subsequently again lowered (solid curves). The spectra are averaged over three pump pulses. b) Cavity output power versus mean pump power. The dashed lines are guides to the eyes indicating a lasing threshold of around 500mW in the mean pump power.

Equations (4)

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

Δ λ = λ χ Δ χ λ 2 2 π a tan 1 ( n 2 1 ) 1 2 ( n 2 1 ) 1 2 ,
ω vib = γ vib ( vib 1 ) ( vib + 2 ) ρ a 3 , vib = 2 , 3 , 4 ,
Q 1 = Q rad 1 + Q abs 1 + Q vib 1 .
Q abs = 2 π n α λ = χ α a

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