Abstract

The suggestive idea of “cloaking” an electromagnetic sensor, i.e., strongly reducing its visibility (scattering) while maintaining its field-sensing (absorption) capabilities, has recently been proposed in the literature, based on scattering-cancellation, Fano-resonance, or transformation-optics approaches. In this paper, we explore an alternative transformation-optics-based route, which relies on the recently introduced concept of “anti-cloaking.” More specifically, our proposed approach relies on a suitable tailoring of the competing cloaking and anti-cloaking mechanisms, interacting in a two-dimensional cylindrical scenario. Via analytical and parametric studies, we illustrate the underlying phenomenology, identify the critical design parameters, and address the relevant optimality and trade-off issues, taking also into account the effect of material losses. Our results confirm the envisaged potentials of the proposed transformation-optics approach as an attractive alternative route to sensor cloaking.

© 2010 Optical Society of America

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    [CrossRef]
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    [CrossRef]
  3. G. W. Milton and N. A. P. Nicorovici, “On the cloaking effects associated with anomalous localized resonance,” Proc. R. Soc. London, Ser. A 462, 3027–3059 (2006).
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  5. J. B. Pendry, D. Schurig, and D. R. Smith, “Controlling electromagnetic fields,” Science 312, 1780–1782 (2006).
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  6. A. Håkansson, “Cloaking of objects from electromagnetic fields by inverse design of scattering optical elements,” Opt. Express 15, 4328–4334 (2007).
    [CrossRef] [PubMed]
  7. P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
    [CrossRef]
  8. I. I. Smolyaninov, V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, “Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking,” Phys. Rev. Lett. 102, 213901 (2009).
    [CrossRef] [PubMed]
  9. D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
    [CrossRef] [PubMed]
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  11. S. Tretyakov, P. Alitalo, O. Luukkonen, and C. Simovski, “Broadband electromagnetic cloaking of long cylindrical objects,” Phys. Rev. Lett. 103, 103905 (2009).
    [CrossRef] [PubMed]
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  17. L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  36. Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
    [CrossRef]
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    [CrossRef]
  39. S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
    [CrossRef]
  40. W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
    [CrossRef]
  41. I. Gallina, G. Castaldi, and V. Galdi, “A higher-order optical transformation for nonmagnetic cloaking,” Microwave Opt. Technol. Lett. 50, 3186–3190 (2008).
    [CrossRef]
  42. L. Zhang, M. Yan, and M. Qiu, “The effect of transformation order on the invisibility performance of a practical cylindrical cloak,” J. Opt. A, Pure Appl. Opt. 10, 095001 (2008).
    [CrossRef]
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  44. I. Gallina, G. Castaldi, V. Galdi, A. Alù, and N. Engheta, “General class of metamaterial transformation slabs,” Phys. Rev. B 81, 125124 (2010).
    [CrossRef]
  45. M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
    [CrossRef]

2010 (4)

T. Ergin, N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, “Three-dimensional invisibility cloak at optical wavelengths,” Science 328, 337–339 (2010).
[CrossRef] [PubMed]

H. F. Ma and T. J. Cui, “Three-dimensional broadband ground-plane cloak made of metamaterials,” Nature Commun. 1, 1–6 (2010).
[CrossRef]

Z. Ruan and S. Fan, “Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle,” J. Phys. Chem. C 114, 7324–7329 (2010).
[CrossRef]

I. Gallina, G. Castaldi, V. Galdi, A. Alù, and N. Engheta, “General class of metamaterial transformation slabs,” Phys. Rev. B 81, 125124 (2010).
[CrossRef]

2009 (15)

G. Castaldi, I. Gallina, and V. Galdi, “Nearly perfect nonmagnetic invisibility cloaking: Analytic solutions and parametric studies,” Phys. Rev. B 80, 125116 (2009).
[CrossRef]

G. Castaldi, I. Gallina, V. Galdi, A. Alù, and N. Engheta, “Cloak/anti-cloak interactions,” Opt. Express 17, 3101–3114 (2009).
[CrossRef] [PubMed]

A. Alù and N. Engheta, “Cloaking a sensor,” Phys. Rev. Lett. 102, 233901 (2009).
[CrossRef] [PubMed]

H. Ma, S. Qu, Z. Xu, and J. Wang, “The open cloak,” Appl. Phys. Lett. 94, 103501 (2009).
[CrossRef]

Y. Lai, H. Chen, Z.-Q. Zhang, and C. T. Chan, “Complementary media invisibility cloak that cloaks objects at a distance outside the cloaking shell,” Phys. Rev. Lett. 102, 093901 (2009).
[CrossRef] [PubMed]

J. Ng, H. Chen, and C. T. Chan, “Metamaterial frequency-selective superabsorber,” Opt. Lett. 34, 644–646 (2009).
[CrossRef] [PubMed]

H. Chen, C. T. Chan, S. Liu, and Z. Lin, “A simple route to a tunable electromagnetic gateway,” New J. Phys. 11, 083012 (2009).
[CrossRef]

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

I. I. Smolyaninov, V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, “Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking,” Phys. Rev. Lett. 102, 213901 (2009).
[CrossRef] [PubMed]

S. Tretyakov, P. Alitalo, O. Luukkonen, and C. Simovski, “Broadband electromagnetic cloaking of long cylindrical objects,” Phys. Rev. Lett. 103, 103905 (2009).
[CrossRef] [PubMed]

B. Edwards, A. Alù, M. G. Silveirinha, and N. Engheta, “Experimental verification of plasmonic cloaking at microwave frequencies,” Phys. Rev. Lett. 103, 153901 (2009).
[CrossRef] [PubMed]

U. Leonhardt and T. G. Philbin, “Transformation optics and the geometry of light,” Prog. Opt. 53, 69–152 (2009).
[CrossRef]

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
[CrossRef]

J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

2008 (13)

J. Li and J. B. Pendry, “Hiding under the carpet: A new strategy for cloaking,” Phys. Rev. Lett. 101, 203901 (2008).
[CrossRef] [PubMed]

V. M. Shalaev, “Transforming light,” Science 322, 384–386 (2008).
[CrossRef] [PubMed]

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

I. I. Smolyaninov, Y. J. Hung, and C. C. Davis, “Two-dimensional metamaterial structure exhibiting reduced visibility at 500 nm,” Opt. Lett. 33, 1342–1344 (2008).
[CrossRef] [PubMed]

M. G. Silveirinha, A. Alù, and N. Engheta, “Cloaking mechanism with antiphase plasmonic satellites,” Phys. Rev. B 78, 205109 (2008).
[CrossRef]

H. Chen, X. Luo, H. Ma, and C. T. Chan, “The anti-cloak,” Opt. Express 16, 14603–14608 (2008).
[CrossRef] [PubMed]

B. Zhang, H. Chen, B. I. Wu, and J. A. Kong, “Extraordinary surface voltage effect in the invisibility cloak with an active device inside,” Phys. Rev. Lett. 100, 063904 (2008).
[CrossRef] [PubMed]

T. Yang, H. Chen, X. Luo, and H. Ma, “Superscatterer: Enhancement of scattering with complementary media,” Opt. Express 16, 18545–18550 (2008).
[CrossRef] [PubMed]

Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
[CrossRef]

Y. Luo, J. Zhang, H. Chen, S. Xi, and B.-I. Wu, “Cylindrical cloak with axial permittivity/permeability spatially invariant,” Appl. Phys. Lett. 93, 033504 (2008).
[CrossRef]

I. Gallina, G. Castaldi, and V. Galdi, “A higher-order optical transformation for nonmagnetic cloaking,” Microwave Opt. Technol. Lett. 50, 3186–3190 (2008).
[CrossRef]

L. Zhang, M. Yan, and M. Qiu, “The effect of transformation order on the invisibility performance of a practical cylindrical cloak,” J. Opt. A, Pure Appl. Opt. 10, 095001 (2008).
[CrossRef]

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

2007 (5)

W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
[CrossRef]

H. S. Chen, B. I. Wu, B. Zhang, and J. A. Kong, “Electromagnetic wave interactions with a metamaterial cloak,” Phys. Rev. Lett. 99, 063903 (2007).
[CrossRef] [PubMed]

Z. Ruan, M. Yan, C. W. Neff, and M. Qiu, “Ideal cylindrical cloak: Perfect but sensitive to tiny perturbations,” Phys. Rev. Lett. 99, 113903 (2007).
[CrossRef] [PubMed]

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

A. Håkansson, “Cloaking of objects from electromagnetic fields by inverse design of scattering optical elements,” Opt. Express 15, 4328–4334 (2007).
[CrossRef] [PubMed]

2006 (5)

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

G. W. Milton and N. A. P. Nicorovici, “On the cloaking effects associated with anomalous localized resonance,” Proc. R. Soc. London, Ser. A 462, 3027–3059 (2006).
[CrossRef]

U. Leonhardt, “Optical conformal mapping,” Science 312, 1777–1780 (2006).
[CrossRef] [PubMed]

J. B. Pendry, D. Schurig, and D. R. Smith, “Controlling electromagnetic fields,” Science 312, 1780–1782 (2006).
[CrossRef] [PubMed]

S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
[CrossRef]

2005 (1)

A. Alù and N. Engheta, “Achieving transparency with plasmonic and metamaterial coatings,” Phys. Rev. E 72, 016623 (2005).
[CrossRef]

Abramowitz, M.

M. Abramowitz and I. A. Stegun, Handbook of Mathematical Functions, 9th printing (Dover, 1970).

Alitalo, P.

S. Tretyakov, P. Alitalo, O. Luukkonen, and C. Simovski, “Broadband electromagnetic cloaking of long cylindrical objects,” Phys. Rev. Lett. 103, 103905 (2009).
[CrossRef] [PubMed]

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

Alù, A.

I. Gallina, G. Castaldi, V. Galdi, A. Alù, and N. Engheta, “General class of metamaterial transformation slabs,” Phys. Rev. B 81, 125124 (2010).
[CrossRef]

B. Edwards, A. Alù, M. G. Silveirinha, and N. Engheta, “Experimental verification of plasmonic cloaking at microwave frequencies,” Phys. Rev. Lett. 103, 153901 (2009).
[CrossRef] [PubMed]

A. Alù and N. Engheta, “Cloaking a sensor,” Phys. Rev. Lett. 102, 233901 (2009).
[CrossRef] [PubMed]

G. Castaldi, I. Gallina, V. Galdi, A. Alù, and N. Engheta, “Cloak/anti-cloak interactions,” Opt. Express 17, 3101–3114 (2009).
[CrossRef] [PubMed]

M. G. Silveirinha, A. Alù, and N. Engheta, “Cloaking mechanism with antiphase plasmonic satellites,” Phys. Rev. B 78, 205109 (2008).
[CrossRef]

A. Alù and N. Engheta, “Achieving transparency with plasmonic and metamaterial coatings,” Phys. Rev. E 72, 016623 (2005).
[CrossRef]

Bartal, G.

J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

Brenner, P.

T. Ergin, N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, “Three-dimensional invisibility cloak at optical wavelengths,” Science 328, 337–339 (2010).
[CrossRef] [PubMed]

Cai, W.

W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
[CrossRef]

Cardenas, J.

L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
[CrossRef]

Castaldi, G.

I. Gallina, G. Castaldi, V. Galdi, A. Alù, and N. Engheta, “General class of metamaterial transformation slabs,” Phys. Rev. B 81, 125124 (2010).
[CrossRef]

G. Castaldi, I. Gallina, and V. Galdi, “Nearly perfect nonmagnetic invisibility cloaking: Analytic solutions and parametric studies,” Phys. Rev. B 80, 125116 (2009).
[CrossRef]

G. Castaldi, I. Gallina, V. Galdi, A. Alù, and N. Engheta, “Cloak/anti-cloak interactions,” Opt. Express 17, 3101–3114 (2009).
[CrossRef] [PubMed]

I. Gallina, G. Castaldi, and V. Galdi, “A higher-order optical transformation for nonmagnetic cloaking,” Microwave Opt. Technol. Lett. 50, 3186–3190 (2008).
[CrossRef]

Chan, C. T.

Y. Lai, H. Chen, Z.-Q. Zhang, and C. T. Chan, “Complementary media invisibility cloak that cloaks objects at a distance outside the cloaking shell,” Phys. Rev. Lett. 102, 093901 (2009).
[CrossRef] [PubMed]

J. Ng, H. Chen, and C. T. Chan, “Metamaterial frequency-selective superabsorber,” Opt. Lett. 34, 644–646 (2009).
[CrossRef] [PubMed]

H. Chen, C. T. Chan, S. Liu, and Z. Lin, “A simple route to a tunable electromagnetic gateway,” New J. Phys. 11, 083012 (2009).
[CrossRef]

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

H. Chen, X. Luo, H. Ma, and C. T. Chan, “The anti-cloak,” Opt. Express 16, 14603–14608 (2008).
[CrossRef] [PubMed]

Chen, H.

Y. Lai, H. Chen, Z.-Q. Zhang, and C. T. Chan, “Complementary media invisibility cloak that cloaks objects at a distance outside the cloaking shell,” Phys. Rev. Lett. 102, 093901 (2009).
[CrossRef] [PubMed]

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

J. Ng, H. Chen, and C. T. Chan, “Metamaterial frequency-selective superabsorber,” Opt. Lett. 34, 644–646 (2009).
[CrossRef] [PubMed]

H. Chen, C. T. Chan, S. Liu, and Z. Lin, “A simple route to a tunable electromagnetic gateway,” New J. Phys. 11, 083012 (2009).
[CrossRef]

H. Chen, X. Luo, H. Ma, and C. T. Chan, “The anti-cloak,” Opt. Express 16, 14603–14608 (2008).
[CrossRef] [PubMed]

T. Yang, H. Chen, X. Luo, and H. Ma, “Superscatterer: Enhancement of scattering with complementary media,” Opt. Express 16, 18545–18550 (2008).
[CrossRef] [PubMed]

B. Zhang, H. Chen, B. I. Wu, and J. A. Kong, “Extraordinary surface voltage effect in the invisibility cloak with an active device inside,” Phys. Rev. Lett. 100, 063904 (2008).
[CrossRef] [PubMed]

Y. Luo, J. Zhang, H. Chen, S. Xi, and B.-I. Wu, “Cylindrical cloak with axial permittivity/permeability spatially invariant,” Appl. Phys. Lett. 93, 033504 (2008).
[CrossRef]

Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
[CrossRef]

Chen, H. S.

H. S. Chen, B. I. Wu, B. Zhang, and J. A. Kong, “Electromagnetic wave interactions with a metamaterial cloak,” Phys. Rev. Lett. 99, 063903 (2007).
[CrossRef] [PubMed]

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

Chettiar, U. K.

W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
[CrossRef]

Chin, J. Y.

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

Cui, T. J.

H. F. Ma and T. J. Cui, “Three-dimensional broadband ground-plane cloak made of metamaterials,” Nature Commun. 1, 1–6 (2010).
[CrossRef]

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

Cummer, S. A.

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

Davis, C. C.

Edwards, B.

B. Edwards, A. Alù, M. G. Silveirinha, and N. Engheta, “Experimental verification of plasmonic cloaking at microwave frequencies,” Phys. Rev. Lett. 103, 153901 (2009).
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B. Edwards, A. Alù, M. G. Silveirinha, and N. Engheta, “Experimental verification of plasmonic cloaking at microwave frequencies,” Phys. Rev. Lett. 103, 153901 (2009).
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A. Alù and N. Engheta, “Cloaking a sensor,” Phys. Rev. Lett. 102, 233901 (2009).
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M. G. Silveirinha, A. Alù, and N. Engheta, “Cloaking mechanism with antiphase plasmonic satellites,” Phys. Rev. B 78, 205109 (2008).
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A. Alù and N. Engheta, “Achieving transparency with plasmonic and metamaterial coatings,” Phys. Rev. E 72, 016623 (2005).
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T. Ergin, N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, “Three-dimensional invisibility cloak at optical wavelengths,” Science 328, 337–339 (2010).
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Z. Ruan and S. Fan, “Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle,” J. Phys. Chem. C 114, 7324–7329 (2010).
[CrossRef]

Gabrielli, L. H.

L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
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Galdi, V.

I. Gallina, G. Castaldi, V. Galdi, A. Alù, and N. Engheta, “General class of metamaterial transformation slabs,” Phys. Rev. B 81, 125124 (2010).
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G. Castaldi, I. Gallina, and V. Galdi, “Nearly perfect nonmagnetic invisibility cloaking: Analytic solutions and parametric studies,” Phys. Rev. B 80, 125116 (2009).
[CrossRef]

G. Castaldi, I. Gallina, V. Galdi, A. Alù, and N. Engheta, “Cloak/anti-cloak interactions,” Opt. Express 17, 3101–3114 (2009).
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I. Gallina, G. Castaldi, and V. Galdi, “A higher-order optical transformation for nonmagnetic cloaking,” Microwave Opt. Technol. Lett. 50, 3186–3190 (2008).
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I. Gallina, G. Castaldi, V. Galdi, A. Alù, and N. Engheta, “General class of metamaterial transformation slabs,” Phys. Rev. B 81, 125124 (2010).
[CrossRef]

G. Castaldi, I. Gallina, and V. Galdi, “Nearly perfect nonmagnetic invisibility cloaking: Analytic solutions and parametric studies,” Phys. Rev. B 80, 125116 (2009).
[CrossRef]

G. Castaldi, I. Gallina, V. Galdi, A. Alù, and N. Engheta, “Cloak/anti-cloak interactions,” Opt. Express 17, 3101–3114 (2009).
[CrossRef] [PubMed]

I. Gallina, G. Castaldi, and V. Galdi, “A higher-order optical transformation for nonmagnetic cloaking,” Microwave Opt. Technol. Lett. 50, 3186–3190 (2008).
[CrossRef]

Greenleaf, A.

A. Greenleaf, Y. Kurylev, M. Lassas, and G. Uhlmann, “Cloaking vs. shielding in transformation optics,” arXiv:0912.1872.

Håkansson, A.

Han, D.

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

Hung, Y. J.

Ji, C.

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

Justice, B. J.

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

Jylha, L.

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

Kildishev, A. V.

I. I. Smolyaninov, V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, “Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking,” Phys. Rev. Lett. 102, 213901 (2009).
[CrossRef] [PubMed]

W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
[CrossRef]

Kong, J. A.

B. Zhang, H. Chen, B. I. Wu, and J. A. Kong, “Extraordinary surface voltage effect in the invisibility cloak with an active device inside,” Phys. Rev. Lett. 100, 063904 (2008).
[CrossRef] [PubMed]

Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
[CrossRef]

H. S. Chen, B. I. Wu, B. Zhang, and J. A. Kong, “Electromagnetic wave interactions with a metamaterial cloak,” Phys. Rev. Lett. 99, 063903 (2007).
[CrossRef] [PubMed]

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

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A. Greenleaf, Y. Kurylev, M. Lassas, and G. Uhlmann, “Cloaking vs. shielding in transformation optics,” arXiv:0912.1872.

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Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

Y. Lai, H. Chen, Z.-Q. Zhang, and C. T. Chan, “Complementary media invisibility cloak that cloaks objects at a distance outside the cloaking shell,” Phys. Rev. Lett. 102, 093901 (2009).
[CrossRef] [PubMed]

Lassas, M.

A. Greenleaf, Y. Kurylev, M. Lassas, and G. Uhlmann, “Cloaking vs. shielding in transformation optics,” arXiv:0912.1872.

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U. Leonhardt and T. G. Philbin, “Transformation optics and the geometry of light,” Prog. Opt. 53, 69–152 (2009).
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J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

J. Li and J. B. Pendry, “Hiding under the carpet: A new strategy for cloaking,” Phys. Rev. Lett. 101, 203901 (2008).
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H. Chen, C. T. Chan, S. Liu, and Z. Lin, “A simple route to a tunable electromagnetic gateway,” New J. Phys. 11, 083012 (2009).
[CrossRef]

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L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
[CrossRef]

Liu, R.

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

Liu, S.

H. Chen, C. T. Chan, S. Liu, and Z. Lin, “A simple route to a tunable electromagnetic gateway,” New J. Phys. 11, 083012 (2009).
[CrossRef]

Luo, X.

Luo, Y.

Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
[CrossRef]

Y. Luo, J. Zhang, H. Chen, S. Xi, and B.-I. Wu, “Cylindrical cloak with axial permittivity/permeability spatially invariant,” Appl. Phys. Lett. 93, 033504 (2008).
[CrossRef]

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

Luukkonen, O.

S. Tretyakov, P. Alitalo, O. Luukkonen, and C. Simovski, “Broadband electromagnetic cloaking of long cylindrical objects,” Phys. Rev. Lett. 103, 103905 (2009).
[CrossRef] [PubMed]

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

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Ma, H. F.

H. F. Ma and T. J. Cui, “Three-dimensional broadband ground-plane cloak made of metamaterials,” Nature Commun. 1, 1–6 (2010).
[CrossRef]

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W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
[CrossRef]

G. W. Milton and N. A. P. Nicorovici, “On the cloaking effects associated with anomalous localized resonance,” Proc. R. Soc. London, Ser. A 462, 3027–3059 (2006).
[CrossRef]

Mock, J. J.

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

Neff, C. W.

Z. Ruan, M. Yan, C. W. Neff, and M. Qiu, “Ideal cylindrical cloak: Perfect but sensitive to tiny perturbations,” Phys. Rev. Lett. 99, 113903 (2007).
[CrossRef] [PubMed]

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J. Ng, H. Chen, and C. T. Chan, “Metamaterial frequency-selective superabsorber,” Opt. Lett. 34, 644–646 (2009).
[CrossRef] [PubMed]

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

Nicorovici, N. A. P.

G. W. Milton and N. A. P. Nicorovici, “On the cloaking effects associated with anomalous localized resonance,” Proc. R. Soc. London, Ser. A 462, 3027–3059 (2006).
[CrossRef]

Pendry, J.

S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
[CrossRef]

Pendry, J. B.

T. Ergin, N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, “Three-dimensional invisibility cloak at optical wavelengths,” Science 328, 337–339 (2010).
[CrossRef] [PubMed]

J. Li and J. B. Pendry, “Hiding under the carpet: A new strategy for cloaking,” Phys. Rev. Lett. 101, 203901 (2008).
[CrossRef] [PubMed]

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

J. B. Pendry, D. Schurig, and D. R. Smith, “Controlling electromagnetic fields,” Science 312, 1780–1782 (2006).
[CrossRef] [PubMed]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

Philbin, T. G.

U. Leonhardt and T. G. Philbin, “Transformation optics and the geometry of light,” Prog. Opt. 53, 69–152 (2009).
[CrossRef]

Poitras, C. B.

L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
[CrossRef]

Popa, B. -I.

S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
[CrossRef]

Qiu, M.

L. Zhang, M. Yan, and M. Qiu, “The effect of transformation order on the invisibility performance of a practical cylindrical cloak,” J. Opt. A, Pure Appl. Opt. 10, 095001 (2008).
[CrossRef]

Z. Ruan, M. Yan, C. W. Neff, and M. Qiu, “Ideal cylindrical cloak: Perfect but sensitive to tiny perturbations,” Phys. Rev. Lett. 99, 113903 (2007).
[CrossRef] [PubMed]

Qu, S.

H. Ma, S. Qu, Z. Xu, and J. Wang, “The open cloak,” Appl. Phys. Lett. 94, 103501 (2009).
[CrossRef]

Rahm, M.

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

Ran, L.

Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
[CrossRef]

Ran, L. X.

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

Roberts, D. A.

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

Ruan, Z.

Z. Ruan and S. Fan, “Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle,” J. Phys. Chem. C 114, 7324–7329 (2010).
[CrossRef]

Z. Ruan, M. Yan, C. W. Neff, and M. Qiu, “Ideal cylindrical cloak: Perfect but sensitive to tiny perturbations,” Phys. Rev. Lett. 99, 113903 (2007).
[CrossRef] [PubMed]

Schurig, D.

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

J. B. Pendry, D. Schurig, and D. R. Smith, “Controlling electromagnetic fields,” Science 312, 1780–1782 (2006).
[CrossRef] [PubMed]

Shalaev, V. M.

I. I. Smolyaninov, V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, “Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking,” Phys. Rev. Lett. 102, 213901 (2009).
[CrossRef] [PubMed]

V. M. Shalaev, “Transforming light,” Science 322, 384–386 (2008).
[CrossRef] [PubMed]

W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, andG. W. Milton, “Nonmagnetic cloak with minimized scattering,” Appl. Phys. Lett. 91, 111105 (2007).
[CrossRef]

Silveirinha, M. G.

B. Edwards, A. Alù, M. G. Silveirinha, and N. Engheta, “Experimental verification of plasmonic cloaking at microwave frequencies,” Phys. Rev. Lett. 103, 153901 (2009).
[CrossRef] [PubMed]

M. G. Silveirinha, A. Alù, and N. Engheta, “Cloaking mechanism with antiphase plasmonic satellites,” Phys. Rev. B 78, 205109 (2008).
[CrossRef]

Simovski, C.

S. Tretyakov, P. Alitalo, O. Luukkonen, and C. Simovski, “Broadband electromagnetic cloaking of long cylindrical objects,” Phys. Rev. Lett. 103, 103905 (2009).
[CrossRef] [PubMed]

Smith, D. R.

R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plane cloak,” Science 323, 366–369 (2009).
[CrossRef] [PubMed]

M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
[CrossRef]

S. A. Cummer, B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, “Full-wave simulations of electromagnetic cloaking structures,” Phys. Rev. E 74, 036621 (2006).
[CrossRef]

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

J. B. Pendry, D. Schurig, and D. R. Smith, “Controlling electromagnetic fields,” Science 312, 1780–1782 (2006).
[CrossRef] [PubMed]

Smolyaninov, I. I.

I. I. Smolyaninov, V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, “Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking,” Phys. Rev. Lett. 102, 213901 (2009).
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I. I. Smolyaninov, Y. J. Hung, and C. C. Davis, “Two-dimensional metamaterial structure exhibiting reduced visibility at 500 nm,” Opt. Lett. 33, 1342–1344 (2008).
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I. I. Smolyaninov, V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, “Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking,” Phys. Rev. Lett. 102, 213901 (2009).
[CrossRef] [PubMed]

Starr, A. F.

D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, “Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977–980 (2006).
[CrossRef] [PubMed]

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M. Abramowitz and I. A. Stegun, Handbook of Mathematical Functions, 9th printing (Dover, 1970).

Stenger, N.

T. Ergin, N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, “Three-dimensional invisibility cloak at optical wavelengths,” Science 328, 337–339 (2010).
[CrossRef] [PubMed]

Tretyakov, S.

S. Tretyakov, P. Alitalo, O. Luukkonen, and C. Simovski, “Broadband electromagnetic cloaking of long cylindrical objects,” Phys. Rev. Lett. 103, 103905 (2009).
[CrossRef] [PubMed]

Tretyakov, S. A.

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

Uhlmann, G.

A. Greenleaf, Y. Kurylev, M. Lassas, and G. Uhlmann, “Cloaking vs. shielding in transformation optics,” arXiv:0912.1872.

Valentine, J.

J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

Venermo, J.

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

Wang, J.

H. Ma, S. Qu, Z. Xu, and J. Wang, “The open cloak,” Appl. Phys. Lett. 94, 103501 (2009).
[CrossRef]

Wegener, M.

T. Ergin, N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, “Three-dimensional invisibility cloak at optical wavelengths,” Science 328, 337–339 (2010).
[CrossRef] [PubMed]

Wu, B. I.

B. Zhang, H. Chen, B. I. Wu, and J. A. Kong, “Extraordinary surface voltage effect in the invisibility cloak with an active device inside,” Phys. Rev. Lett. 100, 063904 (2008).
[CrossRef] [PubMed]

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

H. S. Chen, B. I. Wu, B. Zhang, and J. A. Kong, “Electromagnetic wave interactions with a metamaterial cloak,” Phys. Rev. Lett. 99, 063903 (2007).
[CrossRef] [PubMed]

Wu, B. -I.

Y. Luo, J. Zhang, H. Chen, S. Xi, and B.-I. Wu, “Cylindrical cloak with axial permittivity/permeability spatially invariant,” Appl. Phys. Lett. 93, 033504 (2008).
[CrossRef]

Xi, S.

Y. Luo, J. Zhang, H. Chen, S. Xi, and B.-I. Wu, “Cylindrical cloak with axial permittivity/permeability spatially invariant,” Appl. Phys. Lett. 93, 033504 (2008).
[CrossRef]

Xiao, J.

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

Xu, Z.

H. Ma, S. Qu, Z. Xu, and J. Wang, “The open cloak,” Appl. Phys. Lett. 94, 103501 (2009).
[CrossRef]

Yan, M.

L. Zhang, M. Yan, and M. Qiu, “The effect of transformation order on the invisibility performance of a practical cylindrical cloak,” J. Opt. A, Pure Appl. Opt. 10, 095001 (2008).
[CrossRef]

Z. Ruan, M. Yan, C. W. Neff, and M. Qiu, “Ideal cylindrical cloak: Perfect but sensitive to tiny perturbations,” Phys. Rev. Lett. 99, 113903 (2007).
[CrossRef] [PubMed]

Yang, T.

Zentgraf, T.

J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

Zhang, B.

B. Zhang, H. Chen, B. I. Wu, and J. A. Kong, “Extraordinary surface voltage effect in the invisibility cloak with an active device inside,” Phys. Rev. Lett. 100, 063904 (2008).
[CrossRef] [PubMed]

B. Zhang, H. S. Chen, B. I. Wu, Y. Luo, L. X. Ran, and J. A. Kong, “Response of a cylindrical invisibility cloak to electromagnetic waves,” Phys. Rev. B 76, 121101 (2007).
[CrossRef]

H. S. Chen, B. I. Wu, B. Zhang, and J. A. Kong, “Electromagnetic wave interactions with a metamaterial cloak,” Phys. Rev. Lett. 99, 063903 (2007).
[CrossRef] [PubMed]

Zhang, J.

Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
[CrossRef]

Y. Luo, J. Zhang, H. Chen, S. Xi, and B.-I. Wu, “Cylindrical cloak with axial permittivity/permeability spatially invariant,” Appl. Phys. Lett. 93, 033504 (2008).
[CrossRef]

Zhang, L.

L. Zhang, M. Yan, and M. Qiu, “The effect of transformation order on the invisibility performance of a practical cylindrical cloak,” J. Opt. A, Pure Appl. Opt. 10, 095001 (2008).
[CrossRef]

Zhang, X.

J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

Zhang, Z. -Q.

Y. Lai, J. Ng, H. Chen, D. Han, J. Xiao, Z.-Q. Zhang, and C. T. Chan, “Illusion optics: The optical transformation of an object into another object,” Phys. Rev. Lett. 102, 253902 (2009).
[CrossRef] [PubMed]

Y. Lai, H. Chen, Z.-Q. Zhang, and C. T. Chan, “Complementary media invisibility cloak that cloaks objects at a distance outside the cloaking shell,” Phys. Rev. Lett. 102, 093901 (2009).
[CrossRef] [PubMed]

Appl. Phys. Lett. (3)

H. Ma, S. Qu, Z. Xu, and J. Wang, “The open cloak,” Appl. Phys. Lett. 94, 103501 (2009).
[CrossRef]

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IEEE Trans. Antennas Propag. (1)

P. Alitalo, O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, “Transmission-line networks cloaking objects from electromagnetic fields,” IEEE Trans. Antennas Propag. 56, 416–424 (2008).
[CrossRef]

J. Opt. A, Pure Appl. Opt. (1)

L. Zhang, M. Yan, and M. Qiu, “The effect of transformation order on the invisibility performance of a practical cylindrical cloak,” J. Opt. A, Pure Appl. Opt. 10, 095001 (2008).
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Z. Ruan and S. Fan, “Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle,” J. Phys. Chem. C 114, 7324–7329 (2010).
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Microwave Opt. Technol. Lett. (1)

I. Gallina, G. Castaldi, and V. Galdi, “A higher-order optical transformation for nonmagnetic cloaking,” Microwave Opt. Technol. Lett. 50, 3186–3190 (2008).
[CrossRef]

Nat. Photonics (1)

L. H. Gabrielli, J. Cardenas, C. B. Poitras, and M. Lipson, “Silicon nanostructure cloak operating at optical frequencies,” Nat. Photonics 3, 461–463 (2009).
[CrossRef]

Nature Commun. (1)

H. F. Ma and T. J. Cui, “Three-dimensional broadband ground-plane cloak made of metamaterials,” Nature Commun. 1, 1–6 (2010).
[CrossRef]

Nature Mater. (1)

J. Valentine, J. Li, T. Zentgraf, G. Bartal, and X. Zhang, “An optical cloak made of dielectrics,” Nature Mater. 8, 568–571 (2009).
[CrossRef]

New J. Phys. (1)

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Opt. Express (4)

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M. Rahm, D. Schurig, D. A. Roberts, S. A. Cummer, D. R. Smith, and J. B. Pendry, “Design of electromagnetic cloaks and concentrators using form-invariant coordinate transformations of Maxwell’s equations,” Photonics Nanostruct. Fundam. Appl. 6, 87–95 (2008).
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Phys. Rev. B (5)

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Y. Luo, H. Chen, J. Zhang, L. Ran, and J. A. Kong, “Design and analytical full-wave validation of the invisibility cloaks, concentrators, and field rotators created with a general class of transformations,” Phys. Rev. B 77, 125127 (2008).
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Phys. Rev. E (2)

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Phys. Rev. Lett. (10)

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Figures (10)

Fig. 1
Fig. 1

Problem geometry: A homogeneous metamaterial circular-cylindrical target of radius R 1 and constitutive parameters ε 1 and μ 1 , surrounded by a cloak and anti-cloak cylindrical shells separated by a vacuum gap, in the actual physical space ( x , y , z ) [and associated cylindrical coordinate system ( r , ϕ , z ) ].

Fig. 2
Fig. 2

Geometry as in Fig. 1, with ε ¯ 1 = ( 4 + i 0.25 ) ε 0 , μ 1 = μ 0 , R 1 = λ 0 / 8 , R 2 = λ 0 / 2 , R 3 = ( 1 + Δ G ) R 2 , R 4 = λ 0 , and lossless cloak and anti-cloak. (a)–(c) Total scattering cross-sectional width in Eq. (19) normalized by the reference value in vacuum [cf. Eq. (21)] in decibel scale, as a function of Δ 2 / R 2 and Δ 3 / R 3 , for gap thicknesses Δ G = 0 , 1 / 50 , 1 / 25 , respectively. (d)–(f) Corresponding total absorption cross-sectional width normalized by the reference value in vacuum.

Fig. 3
Fig. 3

Trade-off curves (full markers) pertaining to the lossless cloak/anti-cloak configuration in Fig. 2, for various values of the target loss levels (squares, circles, triangles, diamonds: Im [ ε ¯ 1 ] = 0.25 ε 0 , 0.5 ε 0 , ε 0 , 2 ε 0 , respectively). Also shown (empty markers), as references, are the corresponding curves pertaining to an imperfect (lossless) cloak configuration [cf. Eq. (22)].

Fig. 4
Fig. 4

Geometry and parameters as in Fig. 2. Field map (real part of magnetic field) pertaining to a plane-wave-excited lossless cloak/anti-cloak configuration with Δ G = 0 , Δ 2 / R 2 = 0.118 , Δ 3 / R 3 = 0.03 , featuring Q ¯ s = 20   dB and Q ¯ a = 1.56   dB .

Fig. 5
Fig. 5

Same as in Fig. 4, but for the target free-standing in vacuum.

Fig. 6
Fig. 6

Same as in Fig. 2, but for a lossy cloak ( loss-tangent = 0.001 ) and anti-cloak ( loss-tangent = 0.01 ) configuration. In (d)–(f), the time-averaged dissipative power P a in Eq. (20) (normalized to its free space value P a ( 0 ) ) is considered.

Fig. 7
Fig. 7

Same as in Fig. 3, but for a lossy cloak ( loss-tangent = 0.001 ) and anti-cloak ( loss-tangent = 0.01 ) configuration.

Fig. 8
Fig. 8

Same as in Fig. 4, but for a slightly lossy cloak ( loss-tangent = 0.001 ) and anti-cloak ( loss-tangent = 0.01 ) configuration with Δ G = 0 , Δ 2 / R 2 = 0.158 , Δ 3 / R 3 = 0.028 , featuring Q ¯ s = 20   dB and P ¯ a P a / P a ( 0 ) = 3.13   dB .

Fig. 9
Fig. 9

Same as in Fig. 3, but for increased loss level ( loss-tangent = 0.1 ) in the anti-cloak.

Fig. 10
Fig. 10

Same as in Fig. 4, but for a lossy cloak ( loss-tangent = 0.001 ) and anti-cloak ( loss-tangent = 0.1 ) configuration with Δ G = 0 , Δ 2 / R 2 = 0.315 , Δ 3 / R 3 = 0.037 , featuring Q ¯ s = 15   dB and P ¯ a = 4.44   dB .

Equations (24)

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r = f ( r ) = { r , r < R 1 , r > R 4 R 1 ( R 2 + Δ 2 r R 2 + Δ 2 R 1 ) , R 1 < r < R 2 R 4 ( r R 3 + Δ 3 R 4 R 3 + Δ 3 ) , R 3 < r < R 4 , }
H z ( r , ϕ ) = n = { ( a n ( ν ) + δ ν 5 i n ) J n [ g ( r ) ] + b n ( ν ) Y n [ g ( r ) ] } exp ( i n ϕ ) ,     R ν 1 < r < R ν ,
ν = 1 , , 5.
g ( r ) = { k 0 r , R 2 < r < R 3 ω ϵ [ f ( r ) ] μ [ f ( r ) ] f ( r ) , r < R 2 , r > R 3 , }
b n ( 4 , 5 ) = i a n ( 5 ) ,     a n ( 4 ) = i n + i a n ( 5 ) ,     b n ( 1 , 2 ) = 0 ,     a n ( 2 ) = a n ( 1 ) ,
a 0 ( 1 , 3 , 5 ) b 0 ( 3 ) O ( 1 log   Δ 3 ) ,
a n ( 1 ) O ( Δ 3 | n | Δ 2 | n | ) ,     a n ( 3 ) b n ( 3 ) O ( Δ 3 | n | ) ,
a n ( 5 ) O ( Δ 3 2 | n | ) ,     n > 0 ,
ε ¯ 1 = ( 1 + Δ ε ) 2 ε 1 ,
b ¯ n ( 1 ) = 0 ,     b ¯ n ( 4 , 5 ) = i a ¯ n ( 5 ) ,     a ¯ n ( 4 ) = i n + a ¯ n ( 5 ) ,
b ¯ n ( 2 ) a ¯ n ( 1 ) O ( Δ ε ) ,     a ¯ n ( 2 ) a ¯ n ( 1 ) [ 1 + O ( Δ ε ) ] ,
a ¯ n ( 1 ) a n ( 1 ) 1 + O n ,     { a ¯ n ( 3 , 5 ) b ¯ n ( 3 ) } { a n ( 3 , 5 ) b n ( 3 ) } ( 1 + O n 1 + O n ) ,
O n = { O ( Δ ε   log   Δ 3 ) , n = 0 O ( Δ ε Δ 3 2 | n | ) , n > 0. }
a ¯ n ( 1 ) O ( Δ 3 2 | n | 2 q ) ,     n > q .
R 3 = ( 1 + Δ G ) R 2 ,
a n ( 1 ) { 1 1 + O ( Δ G   log   Δ 3 ) , n = 0 2 i n γ | n | ε 1 ( ε 1 + ε 0 ) ( Δ 3 Δ 2 ) | n | + O ( Δ 3 2 | n | ) + O ( Δ G ) , n 0 , }
a n ( 5 ) { O ( Δ G log 1 Δ 3 ) O ( Δ G ) + O ( log 1 Δ 3 ) , n = 0 O ( Δ 3 2 | n | ) [ 1 + O ( Δ G ) ] , n 0 , }
γ = ε 0 μ 0 R 4 ( R 2 R 1 ) ε 1 μ 1 R 1 ( R 4 R 3 ) .
R 1 Δ 2 R 2 + Δ 2 R 1 = R 4 Δ 3 R 4 + Δ 3 R 3 ,
γ = ε 0 μ 0 ε 1 μ 1 ( Δ 2 Δ 3 ) .
Q s = 2 π n = | a ¯ n ( 5 ) | 2 ,     Q a = 2 π n = { | a ¯ n ( 5 ) | 2 + Re [ i n a ¯ n ( 5 ) ] } .
P a = ω   Im [ ε ¯ 1 ] 2 0 R 1 r d r 0 2 π d ϕ | E ( r , ϕ ) | 2 ,
Q ¯ s Q s Q s ( 0 ) ,     Q ¯ a Q a Q a ( 0 ) .
r = f ( r ) = { r , r < R 1 , r > R 4 R 4 ( r R 1 + Δ 1 R 4 R 1 + Δ 1 ) , R 1 < r < R 4 , }

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