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2015-02-07
Cloaking and Invisibility: a Review (Invited Review)
By
Progress In Electromagnetics Research, Vol. 147, 171-202, 2014
Abstract
Invisibility has been a tantalizing concept for mankind over several centuries. With recent developments in metamaterial science and nanotechnology, the possibility of cloaking objects to incoming electromagnetic radiation has been escaping the realm of science fiction to become a technological reality. In this article, we review the state-of-the-art in the science of invisibility for electromagnetic waves, and examine the different available technical concepts and experimental investigations, focusing on the underlying physics and the basic scientific concepts. We discuss the available cloaking methods, including transformation optics, plasmonic and mantle cloaking, transmission-line networks, parallel-plate cloaking, anomalous resonance methods, hybrid methods and active schemes, and give our perspective on the subject and its future. We also draw a parallel with cloaking research for acoustic and elastodynamic waves, liquid waves, matter waves and thermal flux, demonstrating how ideas initiated in the field of electromagnetism have been able to open groundbreaking venues in a variety of other scientific fields. Finally, applications of cloaking to non-invasive sensing are discussed and reviewed.
Citation
Romain Fleury, and Andrea Alu, "Cloaking and Invisibility: a Review (Invited Review)," Progress In Electromagnetics Research, Vol. 147, 171-202, 2014.
doi:10.2528/PIER15011403
References

1. Caloz, C. and T. Itoh, Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications, John Wiley & Sons, 2005.
doi:10.1002/0471754323

2. Eleftheriades, G. V. and K. G. Balmain, Negative-refraction Metamaterials: Fundamental Principles and Applications, John Wiley & Sons, 2005.
doi:10.1002/0471744751

3. Engheta, N. and R. W. Ziolkowski, Metamaterials: Physics and Engineering Explorations, John Wiley & Sons, 2006.

4. Sarychev, A. K. and V. M. Shalaev, Electrodynamics of Metamaterials, World Scientific, 2007.

5. Cai, W. and V. M. Shalaev, Optical Metamaterials: Fundamentals and Applications, Springer, 2009.

6. Cui, T. J., D. R. Smith, and R. Liu, Metamaterials: Theory, Design, and Applications, Springer, 2009.

7. Capolino, F., Theory and Phenomena of Metamaterials, CRC Press, 2009.
doi:10.1201/9781420054262

8. Capolino, F., Applications of Metamaterials, CRC Press, 2009.
doi:10.1201/9781420054248

9. Marques, R., F. Martin, and M. Sorolla, Metamaterials with Negative Parameters: Theory, Design and Microwave Applications, John Wiley & Sons, 2011.

10. Shvets, G. and I. Tsukerman, Plasmonics and Plasmonic Metamaterials: Analysis and Applications, World Scientific, 2012.

11. Craster, R. V. and S. Guenneau, Acoustic Metamaterials: Negative Refraction, Imaging, Lensing and Cloaking, Springer, 2012.

12. Veselago, V. G., "The electrodynamics of substances with simultaneously negative values of ε and μ," Soviet Physics Uspekhi, Vol. 10, No. 4, 509-514, Apr. 1968.
doi:10.1070/PU1968v010n04ABEH003699

13. Pendry, J. B., "Negative refraction makes a perfect lens," Phys. Rev. Lett., Vol. 85, No. 18, 3966-3969, Oct. 2000.
doi:10.1103/PhysRevLett.85.3966

14. Smith, D. R., W. J. Padilla, D. C. Vier, S. C. Nemat-Nasser, and S. Schultz, "Composite medium with simultaneously negative permeability and permittivity," Phys. Rev. Lett., Vol. 84, No. 18, 4184-4187, May 2000.
doi:10.1103/PhysRevLett.84.4184

15. Pendry, J., "Optics: Positively negative," Nature, Vol. 423, No. 6935, 22-23, May 2003.
doi:10.1038/423022a

16. Smith, D. R., J. B. Pendry, and M. C. K. Wiltshire, "Metamaterials and negative refractive index," Science, Vol. 305, No. 5685, 788-792, Aug. 2004.
doi:10.1126/science.1096796

17. Noginov, M. A., H. Li, Y. A. Barnakov, D. Dryden, G. Nataraj, G. Zhu, C. E. Bonner, M. Mayy, Z. Jacob, and E. E. Narimanov, "Controlling spontaneous emission with metamaterials," Opt. Lett., Vol. 35, No. 11, 1863-1865, Jun. 2010.
doi:10.1364/OL.35.001863

18. Jacob, Z., J.-Y. Kim, G. V. Naik, A. Boltasseva, E. E. Narimanov, and V. M. Shalaev, "Engineering photonic density of states using metamaterials," Appl. Phys. B, Vol. 100, No. 1, 215-218, Jul. 2010.
doi:10.1007/s00340-010-4096-5

19. Alu, A. and N. Engheta, "Boosting molecular fluorescence with a plasmonic nanolauncher," Phys. Rev. Lett., Vol. 103, No. 4, 043902, Jul. 2009.
doi:10.1103/PhysRevLett.103.043902

20. Fleury, R. and A. Alu, "Enhanced superradiance in epsilon-near-zero plasmonic channels," Phys. Rev. B, Vol. 87, No. 20, 201101, May 2013.
doi:10.1103/PhysRevB.87.201101

21. Silveirinha, M. and N. Engheta, "Tunneling of electromagnetic energy through subwavelength channels and bends using ε-near-zero materials," Phys. Rev. Lett., Vol. 97, No. 15, 157403, Oct. 2006.
doi:10.1103/PhysRevLett.97.157403

22. Edwards, B., A. Alu, M. E. Young, M. Silveirinha, and N. Engheta, "Experimental verification of epsilon-near-zero metamaterial coupling and energy squeezing using a microwave waveguide," Phys. Rev. Lett., Vol. 100, No. 3, 033903, Jan. 2008.
doi:10.1103/PhysRevLett.100.033903

23. Fleury, R. and A. Alu, "Extraordinary sound transmission through density-near-zero ultranarrow channels," Phys. Rev. Lett., Vol. 111, No. 5, 055501, Jul. 2013.
doi:10.1103/PhysRevLett.111.055501

24. Alu, A. and N. Engheta, "Pairing an epsilon-negative slab with a mu-negative slab: Resonance, tunneling and transparency," IEEE Trans. Antennas Prop., Vol. 51, No. 10, 2558-2571, Oct. 2003.
doi:10.1109/TAP.2003.817553

25. Alu, A., G. D’Aguanno, N. Mattiucci, and M. J. Bloemer, "Plasmonic brewster angle: Broadband extraordinary transmission through optical gratings," Phys. Rev. Lett., Vol. 106, No. 12, 123902, Mar. 2011.
doi:10.1103/PhysRevLett.106.123902

26. Kerker, M., "Invisible bodies," J. Opt. Soc. Am., Vol. 65, No. 4, 376-379, Apr. 1975.
doi:10.1364/JOSA.65.000376

27. Chew, H. and M. Kerker, "Abnormally low electromagnetic scattering cross sections," J. Opt. Soc. Am., Vol. 66, No. 5, 445-449, May 1976.
doi:10.1364/JOSA.66.000445

28. Hertz, P., "Die Bewegung eines Elektrons unter dem Einflusse einer stets gleich gerichteten Kraft," Math. Ann., Vol. 65, No. 1, 1-86, Mar. 1907.
doi:10.1007/BF01450051

29. Bohm, D. and M. Weinstein, "The self-oscillations of a charged particle," Phys. Rev., Vol. 74, No. 12, 1789-1798, Dec. 1948.
doi:10.1103/PhysRev.74.1789

30. Goedecke, G. H., "Classically radiationless motions and possible implications for quantum theory," Phys. Rev., Vol. 135, No. 1B, B281-B288, Jul. 1964.
doi:10.1103/PhysRev.135.B281

31. Hoenders, B. J., "Existence of invisible nonscattering objects and nonradiating source," J. Opt. Soc. Am. A, Vol. 14, No. 1, 262-266, Jan. 1997.
doi:10.1364/JOSAA.14.000262

32. Boardman, A. D., K. Marinov, N. Zheludev, and V. A. Fedotov, "Dispersion properties of nonradiating configurations: Finite-difference time-domain modeling," Phys. Rev. E, Vol. 72, No. 3, 036603, Sep. 2005.

33. Kahn, W. K. and H. Kurss, "Minimum-scattering antennas," IEEE Trans. Antennas Prop., Vol. 13, No. 5, 671-675, 1965.

34. Alexopoulos, N. G. and N. K. Uzunoglu, "Electromagnetic scattering from active objects: Invisible scatterers," Applied Optics, Vol. 17, No. 2, 235-239, 1978.

35. Kildal, P.-S., A. A. Kishk, and A. Tengs, "Reduction of forward scattering from cylindrical objects using hard surfaces," IEEE Trans. Antennas Prop., Vol. 44, No. 11, 1509-1520, 1996.

36. Devaney, A. J. and G. Sherman, "Nonuniqueness in inverse source and scattering problems," IEEE Trans. Antennas Prop., Vol. 30, No. 5, 1034-1037, 1982.

37. Devaney, A. J., "Nonuniqueness in the inverse scattering problem," Journal of Mathematical Physics, Vol. 19, No. 7, 1526-1531, Aug. 2008.

38. Greenleaf, A., M. Lassas, and G. Uhlmann, "On nonuniqueness for Calder´on’s inverse problem," Mathematical Research Letters, Vol. 10, No. 5, 685-693, 2003.

39. Greenleaf, A., M. Lassas, and G. Uhlmann, "Anisotropic conductivities that cannot be detected by EIT," Physiol. Meas., Vol. 24, No. 2, 413, May 2003.

40. Monticone, F. and A. Alu, "Do cloaked objects really scatter less?," Phys. Rev. X, Vol. 3, No. 4, 041005, Oct. 2013.

41. Monticone, F. and A. Alu, "On the physical bounds of cloaking and invisibility," 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics --- Metamaterials 2013, Bordeaux, France, Sep. 16-21, 2013.

42. Tamm, I. Y., "Electrodynamics of an anisotropic medium in the special theory of relativity," J. Russ. Phys. Chem. Soc., Vol. 56, 248, 1924 (in Russian).

43. Tamm, I. Y., "Crystal-optics of the theory of relativity pertinent to the geometry of a bi-quadratic form," J. Russ. Phys. Chem. Soc., Vol. 56, 1, 1925 (in Russian).

44. Van Dantzig, D., "The fundamental equations of electromagnetism, independent of metrical geometry," Mathematical Proceedings of the Cambridge Philosophical Society, Vol. 30, No. 04, 421-421, 1934.

45. Dolin, L. S., "On a possibility of comparing three-dimensional electromagnetic systems with inhomogeneous filling," Izv. Vyssh. Uchebn. Zaved., Radiofiz., Vol. 4, 964-967, 1961.

46. Post, E. G., Formal Structure of Electromagnetics: General Covariance and Electromagnetics, Interscience Publishers, New York, 1962.

47. Lax, M. and D. F. Nelson, "Maxwell equations in material form," Phys. Rev. B, Vol. 13, No. 4, 1777-1784, Feb. 1976.

48. Ward, A. J. and J. B. Pendry, "Refraction and geometry in Maxwell’s equations," Journal of Modern Optics, Vol. 43, No. 4, 773-793, 1996.

49. Teixeira, F. L. and W. C. Chew, "Lattice electromagnetic theory from a topological viewpoint," Journal of Mathematical Physics, Vol. 40, No. 1, 169-187, Jan. 1999.

50. Teixeira, F. L. and W. C. Chew, "Differential forms, metrics, and the reflectionless absorption of electromagnetic waves," Journal of Electromagnetic Waves and Applications, Vol. 13, No. 5, 665-686, 1999.

51. Leonhardt, U., "Notes on waves with negative phase velocity," IEEE Journal of Selected Topics in Quantum Electronics, Vol. 9, No. 1, 102-105, 2003.

52. Chen, H., B. Hou, S. Chen, X. Ao, W. Wen, and C. T. Chan, "Design and experimental realization of a broadband transformation media field rotator at microwave frequencies," Phys. Rev. Lett., Vol. 102, No. 18, 183903, May 2009.

53. Schurig, D., J. B. Pendry, and D. R. Smith, "Transformation-designed optical elements," Opt. Express, Vol. 15, No. 22, 14772-14782, Oct. 2007.

54. Liu, Y., T. Zentgraf, G. Bartal, and X. Zhang, "Transformational plasmon optics," Nano Lett., Vol. 10, No. 6, 1991-1997, Jun. 2010.

55. Alu, A., F. Bilotti, and L. Vegni, "Generalized transmission line equations for bianisotropic materials," IEEE Trans. Antennas Prop., Vol. 51, No. 11, 3134-3141, Nov. 2003.

56. Alu, A., F. Bilotti, and L. Vegni, "Method of lines numerical analysis of conformal antenna," IEEE Trans. Antennas Prop., Vol. 52, No. 6, 1530-1540, Jun. 2004.

57. Pendry, J. B., D. Schurig, and D. R. Smith, "Controlling electromagnetic fields," Science, Vol. 312, No. 5781, 1780-1782, Jun. 2006.

58. Leonhardt, U., "Optical conformal mapping," Science, Vol. 312, No. 5781, 1777-1780, Jun. 2006.

59. Shalaev, V. M., "Transforming light," Science, Vol. 322, No. 5900, 384-386, Oct. 2008.

60. Greenleaf, A., Y. Kurylev, M. Lassas, and G. Uhlmann, "Cloaking devices, electromagnetic wormholes, and transformation optics," SIAM Review, Vol. 51, No. 1, 3-33, Feb. 2009.

61. Chen, H., C. T. Chan, and P. Sheng, "Transformation optics and metamaterials," Nat. Mater., Vol. 9, No. 5, 387-396, May 2010.

62. Zhang, B., "Electrodynamics of transformation-based invisibility cloaking," Light Sci. Appl., Vol. 1, No. 10, e32, Oct. 2012.

63. Leonhardt, U., "To invisibility and beyond," Nature, Vol. 471, No. 7338, 292-293, Mar. 2011.

64. Wood, B., "Metamaterials and invisibility," Comptes Rendus Physique, Vol. 10, No. 5, 379-390, Jun. 2009.

65. Sheng, P., "Waves on the Horizon," Science, Vol. 313, No. 5792, 1399-1400, Sep. 2006.

66. Leonhardt, U., "Notes on conformal invisibility devices," New J. Phys., Vol. 8, No. 7, 118, Jul. 2006.

67. Schurig, D., J. B. Pendry, and D. R. Smith, "Calculation of material properties and ray tracing in transformation media," Opt. Express, Vol. 14, No. 21, 9794-9804, Oct. 2006.

68. Leonhardt, U. and T. G. Philbin, "General relativity in electrical engineering," New J. Phys., Vol. 8, No. 10, 247, Oct. 2008.

69. Cummer, S. A., B.-I. Popa, D. Schurig, D. R. Smith, and J. Pendry, "Full-wave simulations of electromagnetic cloaking structures," Phys. Rev. E, Vol. 7, No. 4, 036621, Sep. 2006.

70. Zolla, F., S. Guenneau, A. Nicolet, and J. B. Pendry, "Electromagnetic analysis of cylindrical invisibility cloaks and the mirage effect," Opt. Lett., Vol. 32, No. 9, 1069-1071, May 2007.

71. Ruan, Z., M. Yan, C. W. Neff, and M. Qiu, "Ideal cylindrical cloak: Perfect but sensitive to tiny perturbations," Phys. Rev. Lett., Vol. 99, No. 11, 113903, Sep. 2007.

72. Chen, H., B.-I. Wu, B. Zhang, and J. A. Kong, "Electromagnetic wave interactions with a metamaterial cloak," Phys. Rev. Lett., Vol. 99, No. 6, 063903, Aug. 2007.

73. Zhang, B., H. Chen, B.-I.Wu, Y. Luo, L. Ran, and J. A. Kong, "Response of a cylindrical invisibility cloak to electromagnetic waves," Phys. Rev. B, Vol. 76, No. 12, 121101, Sep. 2007.

74. Yaghjian, A. D. and S. Maci, "Alternative derivation of electromagnetic cloaks and concentrators," New J. Phys., Vol. 10, No. 11, 115022, Dec. 2008.

75. Perczel, J., T. Tyc, and U. Leonhardt, "Invisibility cloaking without superluminal propagation," New J. Phys., Vol. 13, No. 8, 083007, Aug. 2011.

76. Sihvola, A., S. Tretyakov, and A. de Baas, "Metamaterials with extreme material parameters," J. Commun. Technol. Electron., Vol. 52, No. 9, 986-990.

77. Alu, A. and N. Engheta, "Extremely anisotropic boundary conditions and their optical applications," Radio Science, Special Issue for URSI EMTS 2010, Vol. 46, RS0E11, Sep. 2011.

78. Alu, A. and N. Engheta, "Optical nanoswitch: An engineered plasmonic nanoparticle with extreme parameters and giant anisotropy," New J. Phys., Vol. 11, No. 1, 013026, Jan. 2009.

79. Alu, A., M. G. Silveirinha, A. Salandrino, and N. Engheta, "Epsilon-near-zero metamaterials and electromagnetic sources: Tailoring the radiation phase pattern," Phys. Rev. B, Vol. 75, No. 15, 155410.

80. Alu, A., M. G. Silveirinha, and N. Engheta, "Transmission-line analysis of ε-near-zero–filled narrow channels," Phys. Rev. E, Vol. 78, No. 1, 016604, Jul. 2008.

81. Ziolkowski, R. W., "Propagation in and scattering from a matched metamaterial having a zero index of refraction," Phys. Rev. E, Vol. 70, No. 4, 046608, Oct. 2004.

82. Alu, A. and N. Engheta, "Coaxial-to-waveguide matching with -near-zero ultranarrow channels and bends," IEEE Trans. Antennas Prop., Vol. 58, No. 2, 328-339, 2010.

83. Alu, A. and N. Engheta, "Optical ‘shorting wires’," Opt. Express, Vol. 15, No. 21, 13773-13782, Oct. 2007.

84. Liu, R., Q. Cheng, T. Hand, J. J.Mock, T. J. Cui, S. A. Cummer, and D. R. Smith, "Experimental demonstration of electromagnetic tunneling through an epsilon-near-zero metamaterial at microwave frequencies," Phys. Rev. Lett., Vol. 100, No. 2, 023903, Jan. 2008.

85. Choi, M., S. H. Lee, Y. Kim, S. B. Kang, J. Shin, M. H. Kwak, K.-Y. Kang, Y.-H. Lee, N. Park, and B. Min, "A terahertz metamaterial with unnaturally high refractive index," Nature, Vol. 470, No. 7334, 369-373, Feb. 2011.

86. Schurig, D., 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, Vol. 314, No. 5801, 977-980, Nov. 2006.

87. Kante, B., D. Germain, and A. de Lustrac, "Experimental demonstration of a nonmagnetic metamaterial cloak at microwave frequencies," Phys. Rev. B, Vol. 80, No. 20, 201104, Nov. 2009.

88. Cai, W., U. K. Chettiar, A. V. Kildishev, and V. M. Shalaev, "Optical cloaking with metamaterials," Nat. Photon., Vol. 1, No. 4, 224-227, Apr. 2007.

89. Cai, W., U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, and G. W. Milton, "Nonmagnetic cloak with minimized scattering," Applied Physics Letters, Vol. 91, No. 11, 111105, Sep. 2007.

90. Cai, W., U. K. Chettiar, A. V. Kildishev, and V. M. Shalaev, "Designs for optical cloaking with high-order transformations," Opt. Express, Vol. 16, No. 8, 5444-5452, Apr. 2008.

91. Yan, M., Z. Ruan, and M. Qiu, "Cylindrical invisibility cloak with simplified material parameters is inherently visible," Phys. Rev. Lett., Vol. 99, No. 23, 233901, Dec. 2007.

92. Chen, H., X. Luo, H. Ma, and C. T. Chan, "The anti-cloak," Opt. Express, Vol. 16, No. 19, 14603-14608, Sep. 2008.

93. Castaldi, G., I. Gallina, V. Galdi, A. Al`u, and N. Engheta, "Analytical study of spherical cloak/anti-cloak interactions," Wave Motion, Vol. 48, No. 6, 455-467, Sep. 2011.

94. Castaldi, G., I. Gallina, V. Galdi, A. Alu, and N. Engheta, "Cloak/anti-cloak interactions," Opt. Express, Vol. 17, No. 5, 3101-3114, Mar. 2009.

95. Leonhardt, U. and T. Tyc, "Broadband invisibility by non-euclidean cloaking," Science, Vol. 323, No. 5910, 110-112, Jan. 2009.

96. Hendi, A., J. Henn, and U. Leonhardt, "Ambiguities in the scattering tomography for central potentials," Phys. Rev. Lett., Vol. 97, No. 7, 073902, Aug. 2006.

97. Halimeh, J. C. and M. Wegener, "Time-of-flight imaging of invisibility cloaks," Opt. Express, Vol. 20, No. 1, 63-74, Jan. 2012.

98. Li, J. and J. B. Pendry, "Hiding under the carpet: A new strategy for cloaking," Phys. Rev. Lett., Vol. 101, No. 20, 203901, Nov. 2008.

99. Dolling, G., M. Wegener, S. Linden, and C. Hormann, "Photorealistic images of objects in effective negative-index materials," Opt. Express, Vol. 14, No. 5, 1842-1849, Mar. 2006.

100. Halimeh, J. C., T. Ergin, J. Mueller, N. Stenger, and M. Wegener, "Photorealistic images of carpet cloaks," Opt. Express, Vol. 17, No. 22, 19328-19336, Oct. 2009.

101. Ergin, T., J. C. Halimeh, N. Stenger, and M. Wegener, "Optical microscopy of 3D carpet cloaks: Ray-tracing calculations," Opt. Express, Vol. 18, No. 19, 20535-20545, Sep. 2010.

102. Danner, A. J., "Visualizing invisibility: Metamaterials-based optical devices in natural environments," Opt. Express, Vol. 18, No. 4, 3332-3337, Feb. 2010.

103. Halimeh, J. C. and M. Wegener, "Photorealistic ray tracing of free-space invisibility cloaks made of uniaxial dielectrics," Opt. Express, Vol. 20, No. 27, 28330-28340, Dec. 2012.

104. Halimeh, J. C. and M. Wegener, "Photorealistic rendering of unidirectional free-space invisibility cloaks," Opt. Express, Vol. 21, No. 8, 9457-9472, Apr. 2013.

105. Zhang, B., T. Chan, and B.-I. Wu, "Lateral shift makes a ground-plane cloak detectable," Phys. Rev. Lett., Vol. 104, No. 23, 233903, Jun. 2010.

106. Landy, N. I., N. Kundtz, and D. R. Smith, "Designing three-dimensional transformation optical media using quasiconformal coordinate transformations," Phys. Rev. Lett., Vol. 105, No. 19, 193902, Nov. 2010.

107. Liu, R., C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, "Broadband ground-plane cloak," Science, Vol. 323, No. 5912, 366-369, Jan. 2009.

108. Valentine, J., J. Li, T. Zentgraf, G. Bartal, and X. Zhang, "An optical cloak made of dielectrics," Nat. Mater., Vol. 8, No. 7, 568-571, Jul. 2009.

109. Lee, J. H., J. Blair, V. A. Tamma, Q. Wu, S. J. Rhee, C. J. Summers, and W. Park, "Direct visualization of optical frequency invisibility cloak based on silicon nanorod array," Opt. Express, Vol. 17, No. 15, 12922-12928, Jul. 2009.

110. Gabrielli, L. H., J. Cardenas, C. B. Poitras, and M. Lipson, "Silicon nanostructure cloak operating at optical frequencies," Nat. Photon., Vol. 3, No. 8, 461-463, Aug. 2009.

111. Ergin, T., N. Stenger, P. Brenner, J. B. Pendry, and M. Wegener, "Three-dimensional invisibility cloak at optical wavelengths," Science, Vol. 328, No. 5976, 337-339, Apr. 2010.

112. Ma, H. F. and T. J. Cui, "Three-dimensional broadband ground-plane cloak made of metamaterials," Nat. Commun., Vol. 1, 21, Jun. 2010.

113. Gharghi, M., C. Gladden, T. Zentgraf, Y. Liu, X. Yin, J. Valentine, and X. Zhang, "A carpet cloak for visible light," Nano Lett., Vol. 11, No. 7, 2825-2828, Jul. 2011.

114. Shin, D., Y. Urzhumov, Y. Jung, G. Kang, S. Baek, M. Choi, H. Park, K. Kim, and D. R. Smith, "Broadband electromagnetic cloaking with smart metamaterials," Nat. Commun., Vol. 3, 1213, Nov. 2012.

115. Smolyaninov, I. I., V. N. Smolyaninova, A. V. Kildishev, and V. M. Shalaev, "Anisotropic metamaterials emulated by tapered waveguides: Application to optical cloaking," Phys. Rev. Lett., Vol. 102, No. 21, 213901, May 2009.

116. Luo, Y., J. Zhang, H. Chen, L. Ran, B.-I. Wu, and J.-A. Kong, "A rigorous analysis of plane-transformed invisibility cloaks," IEEE Trans. Antennas Prop., Vol. 57, No. 12, 3926-3933, 2009.

117. Xi, S., H. Chen, B.-I. Wu, and J.-A. Kong, "One-directional perfect cloak created with homogeneous material," IEEE Microwave and Wireless Components Letters, Vol. 19, No. 3, 131-133, 2009.

118. Zhang, B., Y. Luo, X. Liu, and G. Barbastathis, "Macroscopic invisibility cloak for visible light," Phys. Rev. Lett., Vol. 106, No. 3, 033901, Jan. 2011.

119. Chen, X., Y. Luo, J. Zhang, K. Jiang, J. B. Pendry, and S. Zhang, "Macroscopic invisibility cloaking of visible light," Nat. Commun., Vol. 2, 176, Feb. 2011.

120. Liang, D., J. Gu, J. Han, Y. Yang, S. Zhang, and W. Zhang, "Robust large dimension terahertz cloaking," Advanced Materials, Vol. 24, No. 7, 916-921, 2012.

121. Chen, H. and B. Zheng, "Broadband polygonal invisibility cloak for visible light," Sci. Rep., Vol. 2, 255, 2012.

122. Landy, N. and D. R. Smith, "A full-parameter unidirectional metamaterial cloak for microwaves," Nat. Mater., Vol. 12, No. 1, 25-28, Jan. 2013.

123. Urzhumov, Y., N. Landy, T. Driscoll, D. Basov, and D. R. Smith, "Thin low-loss dielectric coatings for free-space cloaking," Opt. Lett., Vol. 38, No. 10, 1606-1608, May 2013.

124. Chen, H., B. Zheng, L. Shen, H. Wang, X. Zhang, N. I. Zheludev, and B. Zhang, "Ray-optics cloaking devices for large objects in incoherent natural light," Nat. Commun., Vol. 4, Oct. 2013.

125. Howell, J. C. and J. B. Howell, "Simple, broadband, optical spatial cloaking of very large objects,", arXiv e-print 1306.0863, Jun. 2013.

126. Houdin, R., The Secrets of Stage Conjuring, Wildside Press LLC, 2008.

127. Wood, B. and J. B. Pendry, "Metamaterials at zero frequency," J. Phys.: Condens. Matter, Vol. 19, No. 7, 076208, Feb. 2007.

128. Sanchez, A., C. Navau, J. Prat-Camps, and D.-X. Chen, "Antimagnets: Controlling magnetic fields with superconductor–metamaterial hybrids," New J. Phys., Vol. 13, No. 9, 093034, Sep. 2011.

129. Narayana, S. and Y. Sato, "DC magnetic cloak," Advanced Materials, Vol. 24, No. 1, 71-74, 2012.

130. Gomory, F., M. Solovyov, J. Souc, C. Navau, J. Prat-Camps, and A. Sanchez, "Experimental realization of a magnetic cloak," Science, Vol. 335, No. 6075, 1466-1468, Mar. 2012.

131. Souc, J., M. Solovyov, F. Gomory, J. Prat-Camps, C. Navau, and A. Sanchez, "A quasistatic magnetic cloak," New J. Phys., Vol. 15, No. 5, 053019, May 2013.

132. Yang, F., Z. L. Mei, T. Y. Jin, and T. J. Cui, "dc electric invisibility cloak," Phys. Rev. Lett., Vol. 109, No. 5, 053902, Aug. 2012.

133. Liu, M., Z. L. Mei, X. Ma, and T. J. Cui, "dc illusion and its experimental verification," Applied Physics Letters, Vol. 101, No. 5, 051905, Aug. 2012.

134. Mei, Z. L., Y. S. Liu, F. Yang, and T. J. Cui, "A dc carpet cloak based on resistor networks," Opt. Express, Vol. 20, No. 23, 25758-25765, Nov. 2012.

135. Alu, A. and N. Engheta, "Effects of size and frequency dispersion in plasmonic cloaking," Phys. Rev. E, Vol. 78, No. 4, 045602, Oct. 2008.

136. Papas, C. H., Theory of Electromagnetic Wave Propagation, Courier Dover Publications, 2013.

137. Jackson, J. D., Classical Electrodynamics, Wiley, 1998.

138. Bohren, C. F. and D. R. Huffman, Absorption and Scattering of Light by Small Particles, John Wiley & Sons, 2008.

139. Alu, A. and N. Engheta, "Polarizabilities and effective parameters for collections of spherical nanoparticles formed by pairs of concentric double-negative, single-negative, and/or double-positive metamaterial layers," Journal of Applied Physics, Vol. 97, No. 9, 094310, Apr. 2005.

140. Alu, A. and N. Engheta, "Achieving transparency with plasmonic and metamaterial coatings," Phys. Rev. E, Vol. 72, No. 1, 016623, Jul. 2005.

141. Ball, P., "Engineers devise invisibility shield," Nature News, Feb. 2005.

142. Alu, A. and N. Engheta, "Plasmonic and metamaterial cloaking: Physical mechanisms and potentials," J. Opt. A: Pure Appl. Opt., Vol. 10, No. 9, 093002, Sep. 2008.

143. Chen, P.-Y., J. Soric, and A. Alu, "Invisibility and cloaking based on scattering cancellation," Advanced Materials, Vol. 24, No. 44, OP281-OP304, 2012.

144. Alu, A. and N. Engheta, "Plasmonic materials in transparency and cloaking problems: Mechanism, robustness, and physical insights," Opt. Express, Vol. 15, No. 6, 3318-3332, Mar. 2007.

145. Alu, A. and N. Engheta, "Cloaking and transparency for collections of particles with metamaterial and plasmonic covers," Opt. Express, Vol. 15, No. 12, 7578-7590, Jun. 2007.

146. Alu, A. and N. Engheta, "Multifrequency optical invisibility cloak with layered plasmonic shells," Phys. Rev. Lett., Vol. 100, No. 11, 113901, Mar. 2008.

147. Alu, A. and N. Engheta, "Theory and potentials of multi-layered plasmonic covers for multi-frequency cloaking," New J. Phys., Vol. 10, No. 11, 115036, Nov. 2008.

148. Tricarico, S., F. Bilotti, A. Alu, and L. Vegni, "Plasmonic cloaking for irregular objects with anisotropic scattering properties," Phys. Rev. E, Vol. 81, No. 2, 026602, Feb. 2010.

149. Kallos, E., C. Argyropoulos, Y. Hao, and A. Alu, "Comparison of frequency responses of cloaking devices under nonmonochromatic illumination ," Phys. Rev. B, Vol. 84, No. 4, 045102, Jul. 2011.

150. Alu, A., D. Rainwater, and A. Kerkhoff, "Plasmonic cloaking of cylinders: Finite length, oblique illumination and cross-polarization coupling," New J. Phys., Vol. 12, No. 10, 103028, Oct. 2010.

151. Silveirinha, M. G., A. Alu, and N. Enghet, "Cloaking mechanism with antiphase plasmonic satellites," Phys. Rev. B, Vol. 78, No. 20, 205109, Nov. 2008.

152. Silveirinha, M. G., A. Alu, and N. Engheta, "Parallel-plate metamaterials for cloaking structures," Phys. Rev. E, Vol. 75, No. 3, 036603, Mar. 2007.

153. Silveirinha, M. G., A. Alu, and N. Engheta, "Infrared and optical invisibility cloak with plasmonic implants based on scattering cancellation," Phys. Rev. B, Vol. 78, No. 7, 075107, Aug. 2008.

154. Edwards, B., A. Alu, M. G. Silveirinha, and N. Engheta, "Experimental verification of plasmonic cloaking at microwave frequencies with metamaterials," Phys. Rev. Lett., Vol. 103, No. 15, 153901, Oct. 2009.

155. Rainwater, D., A. Kerkhoff, K. Melin, J. C. Soric, G. Moreno, and A. Al, "Experimental verification of three-dimensional plasmonic cloaking in free-space," New J. Phys., Vol. 14, No. 1, 013054, Jan. 2012.

156. Munk, B. A., Frequency Selective Surfaces: Theory and Design, John Wiley & Sons, 2005.

157. Tretyakov, S., Analytical Modeling in Applied Electromagnetics, Artech House, 2003.

158. Alu, A., "Mantle cloak: Invisibility induced by a surface," Phys. Rev. B, Vol. 80, No. 24, 245115, Dec. 2009.

159. Chen, P.-Y. and A. Alu, "Mantle cloaking using thin patterned metasurfaces," Phys. Rev. B, Vol. 84, No. 20, 205110, Nov. 2011.

160. Chen, P.-Y., F. Monticone, and A. Alu, "Suppressing the electromagnetic scattering with an helical mantle cloak," IEEE Antennas and Wireless Propagation Letters, Vol. 10, 1598-1601, 2011.

161. Padooru, Y. R., A. B. Yakovlev, P.-Y. Chen, and A. Alu, "Line-source excitation of realistic conformal metasurface cloaks," Journal of Applied Physics, Vol. 112, No. 10, 104902, Nov. 2012.

162. Padooru, Y. R., A. B. Yakovlev, P.-Y. Chen, and A. Alu, "Analytical modeling of conformal mantle cloaks for cylindrical objects using sub-wavelength printed and slotted arrays," Journal of Applied Physics, Vol. 112, No. 3, 034907, Aug. 2012.

163. Chen, P.-Y. and A. Alu, "Atomically thin surface cloak using graphene monolayers," ACS Nano, Vol. 5, No. 7, 5855-5863, Jul. 2011.

164. Soric, J. C., P. Y. Chen, A. Kerkhoff, D. Rainwater, K. Melin, and A. Alu, "Demonstration of an ultralow profile cloak for scattering suppression of a finite-length rod in free space," New J. Phys., Vol. 15, No. 3, 033037, Mar. 2013.

165. Alitalo, P., O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, "Transmission-line networks cloaking objects from electromagnetic fields," IEEE Trans. Antennas Prop., Vol. 56, No. 2, 416-424, 2008.

166. Alitalo, P., O. Luukkonen, L. Jylha, J. Venermo, and S. A. Tretyakov, "Correction to ‘transmission-line networks cloaking objects from electromagnetic fields’ [Feb. 08, 416–424]," IEEE Trans. Antennas Prop., Vol. 56, No. 3, 918-918, 2008.

167. Alitalo, P., S. Ranvier, J. Vehmas, and S. Tretyakov, "A microwave transmission-line network guiding electromagnetic fields through a dense array of metallic objects," Metamaterials, Vol. 2, No. 4, 206-212, Dec. 2008.

168. Alitalo, P. and S. Tretyakov, "Electromagnetic cloaking with metamaterials," Materials Today, Vol. 12, No. 3, 22-29, Mar. 2009.

169. Alitalo, P., F. Bongard, J.-F. Z¨urcher, J. Mosig, and S. Tretyakov, "Experimental verification of broadband cloaking using a volumetric cloak composed of periodically stacked cylindrical transmission-line networks," Applied Physics Letters, Vol. 94, No. 1, 014103, Jan. 2009.

170. Tretyakov, S., P. Alitalo, O. Luukkonen, and C. Simovski, "Broadband electromagnetic cloaking of long cylindrical objects," Phys. Rev. Lett., Vol. 103, No. 10, 103905, Sep. 2009.

171. Alitalo, P. and S. A. Tretyakov, "Electromagnetic cloaking of strongly scattering cylindrical objects by a volumetric structure composed of conical metal plates," Phys. Rev. B, Vol. 82, No. 24, 245111, Dec. 2010.

172. Alitalo, P., A. E. Culhaoglu, A. V. Osipov, S. Thurner, E. Kemptner, and S. A. Tretyakov, "Bistatic scattering characterization of a three-dimensional broadband cloaking structure," Journal of Applied Physics, Vol. 111, No. 3, 034901-034901-5, 2012.

173. Milton, G. W. and N.-A. P. Nicorovici, "On the cloaking effects associated with anomalous localized resonance," Proc. R. Soc. A, Vol. 462, No. 2074, 3027-3059, Oct. 2006.

174. Milton, G. W., N.-A. P. Nicorovici, R. C. McPhedran, and V. A. Podolskiy, "A proof of superlensing in the quasistatic regime, and limitations of superlenses in this regime due to anomalous localized resonance," Proc. R. Soc. A, Vol. 461, No. 2064, 3999-4034, Dec. 2005.

175. Nicorovici, N. A., G. W. Milton, R. C. McPhedran, and L. C. Botten, "Quasistatic cloaking of two-dimensional polarizable discrete systems by anomalous resonance," Opt. Express, Vol. 15, No. 10, 6314-6323, May 2007.

176. Nicorovici, N.-A. P., R. C. McPhedran, S. Enoch, and G. Tayeb, "Finite wavelength cloaking by plasmonic resonance," New J. Phys., Vol. 10, No. 11, 115020, Nov. 2008.

177. Lai, Y., 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., Vol. 102, No. 9, 093901, Mar. 2009.

178. Zheng, G., X. Heng, and C. Yang, "A phase conjugate mirror inspired approach for building cloaking structures with left-handed materials," New J. Phys., Vol. 11, No. 3, 033010, Mar. 2009.

179. Chen, H., Z. Liang, P. Yao, X. Jiang, H. Ma, and C. T. Chan, "Extending the bandwidth of electromagnetic cloaks," Phys. Rev. B, Vol. 76, No. 24, 241104, Dec. 2007.

180. Miller, D. A. B., "On perfect cloaking," Opt. Express, Vol. 14, No. 25, 12457-12466, Dec. 2006.

181. Greenleaf, A., Y. Kurylev, M. Lassas, and G. Uhlmann, "Full-wave invisibility of active devices at all frequencies," Commun. Math. Phys., Vol. 275, No. 3, 749-789, Nov. 2007.

182. Vasquez, F. G., G. W. Milton, and D. Onofrei, "Active exterior cloaking for the 2D laplace and Helmholtz equations," Phys. Rev. Lett., Vol. 103, No. 7, 073901, Aug. 2009.

183. Guevara Vasquez, F., G. W. Milton, and D. Onofrei, "Broadband exterior cloaking," Opt. Express, Vol. 17, No. 17, 14800-14805, Aug. 2009.

184. Ma, Q., Z. L. Mei, S. K. Zhu, T. Y. Jin, and T. J. Cui, "Experiments on active cloaking and illusion for Laplace equation," Phys. Rev. Lett., Vol. 111, No. 17, 173901, Oct. 2013.

185. Chen, P.-Y., C. Argyropoulos, and A. Alu, "Broadening the cloaking bandwidth with non-foster metasurfaces," Phys. Rev. Lett., Vol. 111, No. 23, 233001, Dec. 2013.

186. Friot, E., R. Guillermin, and M. Winninger, "Active control of scattered acoustic radiation: A real-time implementation for a three-dimensional object," Acta Acustica United with Acustica, Vol. 92, No. 2, 278-288, Mar. 2006.

187. Bender, C. M. and S. Boettcher, "Real spectra in non-hermitian Hamiltonians having PT symmetry," Phys. Rev. Lett., Vol. 80, 5243-5246, 1998.

188. Makris, K. G., R. El-Ganainy, D. N. Christodoulides, and Z. H. Musslimani, "Beam dynamics in PT symmetric optical lattices," Phys. Rev. Lett., Vol. 100, 103904, 2008.

189. Kulishov, M., J. Laniel, N. Belanger, J. Azana, and D. Plant, "Nonreciprocal waveguide Bragg gratings," Opt. Express, Vol. 13, 3068-3078, 2005.

190. Razzari, L. and R. Morandotti, "Optics: Gain and loss mixed in the same cauldron," Nature, Vol. 488, 163-164, 2012.

191. Mostafazadeh, A., "Spectral singularities of complex scattering potentials and infinite reflection and transmission coefficients at real energies," Phys. Rev. Lett., Vol. 102, 220402, 2009.

192. Schomerus, H., "Quantum noise and self-sustained radiation of PT-symmetric systems," Phys. Rev. Lett., Vol. 104, 233601, 2010.

193. Lin, Z., et al. "Unidirectional invisibility induced by PT-symmetric periodic structures," Phys. Rev. Lett., Vol. 106, 213901, 2011.

194. Fleury, R., D. L. Sounas, and A. Alu, "Negative refraction and planar focusing based on parity-time symmetric metasurfaces ," Phys. Rev. Lett., Vol. 113, No. 2, 023903, Jul. 2014.

195. Xu, S., X. Cheng, S. Xi, R. Zhang, H. O. Moser, Z. Shen, Y. Xu, Z. Huang, X. Zhang, F. Yu, B. Zhang, and H. Chen, "Experimental demonstration of a free-space cylindrical cloak without superluminal propagation," Phys. Rev. Lett., Vol. 109, No. 22, 223903, Nov. 2012.

196. Aliev, A. E., Y. N. Gartstein, and R. H. Baughman, "Mirage effect from thermally modulated transparent carbon nanotube sheets," Nanotechnology, Vol. 22, No. 43, 435704, Oct. 2011.

197. Schittny, R., M. Kadic, T. B¨uckmann, and M. Wegener, "Invisibility cloaking in a diffusive light scattering medium," Science, Vol. 345, No. 6195, 427-429, Jun. 2014.

198. Liu, Z., X. Zhang, Y. Mao, Y. Y. Zhu, Z. Yang, C. T. Chan, and P. Sheng, "Locally Resonant Sonic Materials," Science, Vol. 289, No. 5485, 1734-1736, 2000.

199. Li, J. and C. T. Chan, "Double-negative acoustic metamaterial," Phys. Rev. E, Vol. 70, No. 5, 055602, Nov. 2004.

200. Fang, N., D. Xi, J. Xu, M. Ambati, W. Srituravanich, C. Sun, and X. Zhang, "Ultrasonic metamaterials with negative modulus," Nature Materials, Vol. 5, No. 6, 452-456, 2006.

201. Lee, S. H., C. M. Park, Y. M. Seo, Z. G. Wang, and C. K. Kim, "Acoustic metamaterial with negative density," Physics Letters A, Vol. 373, No. 48, 4464-4469, Dec. 2009.

202. Bongard, F., H. Lissek, and J. R. Mosig, "Acoustic transmission line metamaterial with negative/zero/positive refractive index ," Phys. Rev. B, Vol. 82, No. 9, 094306, 2010.

203. Lee, S. H., C. M. Park, Y. M. Seo, Z. G. Wang, and C. K. Kim, "Composite acoustic medium with simultaneously negative density and modulus," Phys. Rev. Lett., Vol. 104, No. 5, 054301, Feb. 2010.

204. Zhou, X. and G. Hu, "Superlensing effect of an anisotropic metamaterial slab with near-zero dynamic mass," Applied Physics Letters, Vol. 98, No. 26, 263510-263510-3, Jul. 2011.

205. Liang, Z. and J. Li, "Extreme acoustic metamaterial by coiling up space," Phys. Rev. Lett., Vol. 108, No. 11, 114301, Mar. 2012.

206. Xie, Y., B.-I. Popa, L. Zigoneanu, and S. A. Cummer, "Measurement of a broadband negative index with space-coiling acoustic metamaterials," Phys. Rev. Lett., Vol. 110, No. 17, 175501, Apr. 2013.

207. Frenzel, T., J. D. Brehm, T. B¨uckmann, R. Schittny, M. Kadic, and M. Wegener, "Three-dimensional labyrinthine acoustic metamaterials," Applied Physics Letters, Vol. 103, No. 6, 061907, Aug. 2013.

208. Yang, M., G. Ma, Z. Yang, and P. Sheng, "Coupled membranes with doubly negative mass density and bulk modulus," Phys. Rev. Lett., Vol. 110, No. 13, 134301, Mar. 2013.

209. Fleury, R. and A. Alu, "Extraordinary sound transmission through density-near-zero ultranarrow channels," Phys. Rev. Lett., Vol. 111, No. 5, 055501, Jul. 2013.

210. Milton, G. W., M. Briane, and J. R. Willis, "On cloaking for elasticity and physical equations with a transformation invariant form," New J. Phys., Vol. 8, No. 10, 248, Oct. 2006.

211. Milton, G. W., "New metamaterials with macroscopic behavior outside that of continuum elastodynamics," New J. Phys., Vol. 9, No. 10, 359, Oct. 2007.

212. Cummer, S. A. and D. Schurig, "One path to acoustic cloaking," New J. Phys., Vol. 9, No. 3, 45, Mar. 2007.

213. Chen, H. and C. T. Chan, "Acoustic cloaking in three dimensions using acoustic metamaterials," Applied Physics Letters, Vol. 91, No. 18, 183518, Nov. 2007.

214. Cummer, S. A., B.-I. Popa, D. Schurig, D. R. Smith, J. Pendry, M. Rahm, and A. Starr, "Scattering theory derivation of a 3D acoustic cloaking shell," Phys. Rev. Lett., Vol. 100, No. 2, 024301, Jan. 2008.

215. Cummer, S. A., M. Rahm, and D. Schurig, "Material parameters and vector scaling in transformation acoustics," New J. Phys., Vol. 10, No. 11, 115025, Nov. 2008.

216. Greenleaf, A., Y. Kurylev, M. Lassas, and G. Uhlmann, "Full-wave invisibility of active devices at all frequencies," Commun. Math. Phys., Vol. 275, No. 3, 749-789, Nov. 2007.

217. Farhat, M., S. Guenneau, S. Enoch, A. Movchan, F. Zolla, and A. Nicolet, "A homogenization route towards square cylindrical acoustic cloaks," New J. Phys., Vol. 10, No. 11, 115030, Nov. 2008.

218. Milton, G. W. and A. V. Cherkaev, "Which elasticity tensors are realizable?," J. Eng. Mater. Technol., Vol. 117, No. 4, 483-493, Oct. 1995.

219. Kadic, M., T. Buckmann, N. Stenger, M. Thiel, and M. Wegener, "On the practicability of pentamode mechanical metamaterials," Applied Physics Letters, Vol. 100, No. 19, 191901, May 2012.

220. Norris, A. N., "Acoustic metafluids," The Journal of the Acoustical Society of America, Vol. 125, No. 2, 839-849, Feb. 2009.

221. Torrent, D. and J. Sanchez-Dehesa, "Anisotropic mass density by two-dimensional acoustic metamaterials," New J. Phys., Vol. 10, No. 2, 023004, Feb. 2008.

222. Torrent, D. and J. Sanchez-Dehesa, "Acoustic cloaking in two dimensions: A feasible approach," New J. Phys., Vol. 10, No. 6, 063015, Jun. 2008.

223. Cheng, Y., F. Yang, J. Y. Xu, and X. J. Liu, "A multilayer structured acoustic cloak with homogeneous isotropic materials," Applied Physics Letters, Vol. 92, No. 15, 151913, Apr. 2008.

224. Munteanu, L. and V. Chiroiu, "On three-dimensional spherical acoustic cloaking," New J. Phys., Vol. 13, No. 8, 083031, Aug. 2011.

225. Urzhumov, Y., F. Ghezzo, J. Hunt, and D. R. Smith, "Acoustic cloaking transformations from attainable material properties," New J. Phys., Vol. 12, No. 7, 073014, Jul. 2010.

226. Zhang, S., C. Xia, and N. Fang, "Broadband acoustic cloak for ultrasound waves," Phys. Rev. Lett., Vol. 106, No. 2, 024301, Jan. 2011.

227. Popa, B.-I., L. Zigoneanu, and S. A. Cummer, "Experimental acoustic ground cloak in air," Phys. Rev. Lett., Vol. 106, No. 25, 253901, Jun. 2011.

228. Farhat, M., S. Guenneau, and S. Enoch, "Ultrabroadband elastic cloaking in thin plates," Phys. Rev. Lett., Vol. 103, No. 2, 024301, Jul. 2009.

229. Brun, M., S. Guenneau, and A. B. Movchan, "Achieving control of in-plane elastic waves," Applied Physics Letters, Vol. 94, No. 6, 061903, Feb. 2009.

230. Stenger, N., M. Wilhelm, and M. Wegener, "Experiments on elastic cloaking in thin plates," Phys. Rev. Lett., Vol. 108, No. 1, 014301, Jan. 2012.

231. Guild, M. D., A. Alu, and M. R. Haberman, "Cancellation of acoustic scattering from an elastic sphere," The Journal of the Acoustical Society of America, Vol. 129, No. 3, 1355-1365, Mar. 2011.

232. Guild, M. D., M. R. Haberman, and A. Alu, "Plasmonic cloaking and scattering cancelation for electromagnetic and acoustic waves," Wave Motion, Vol. 48, No. 6, 468-482, 2011.

233. Guild, M. D., M. R. Haberman, and A. Alu, "Plasmonic-type acoustic cloak made of a bilaminate shell," Phys. Rev. B, Vol. 86, No. 10, 104302, Sep. 2012.

234. Farhat, M., P.-Y. Chen, S. Guenneau, S. Enoch, and A. Alu, "Frequency-selective surface acoustic invisibility for three-dimensional immersed objects," Phys. Rev. B, Vol. 86, No. 17, 174303, Nov. 2012.

235. Sanchis, L., V. M. Garcia-Chocano, R. Llopis-Pontiveros, A. Climente, J. Mart´ınez-Pastor, F. Cervera, and J. Sanchez-Dehesa, "Three-dimensional axisymmetric cloak based on the cancellation of acoustic scattering from a sphere," Phys. Rev. Lett., Vol. 110, No. 12, 124301, Mar. 2013.

236. Martin, T. P. and G. J. Orris, "Hybrid inertial method for broadband scattering reduction," Applied Physics Letters, Vol. 100, No. 3, 033506, Jan. 2012.

237. Li, N., J. Ren, L. Wang, G. Zhang, P. Hanggi, and B. Li, "Colloquium: Phononics: Manipulating heat flow with electronic analogs and beyond," Rev. Mod. Phys., Vol. 84, No. 3, 1045-1066, Jul. 2012.

238. Fan, C. Z., Z., Y. Gao, and J. P. Huang, "Shaped graded materials with an apparent negative thermal conductivity," Applied Physics Letters, Vol. 92, No. 25, 251907, Jun. 2008.

239. Chen, T., C.-N. Weng, and J.-S. Chen, "Cloak for curvilinearly anisotropic media in conduction," Applied Physics Letters, Vol. 93, No. 11, 114103, Sep. 2008.

240. Li, J. Y., Y. Gao, and J. P. Huang, "A bifunctional cloak using transformation media," Journal of Applied Physics, Vol. 108, No. 7, 074504, Oct. 2010.

241. Guenneau, S., C. Amra, and D. Veynante, "Transformation thermodynamics: Cloaking and concentrating heat flux," Opt. Express, Vol. 20, No. 7, 8207-8218, Mar. 2012.

242. Narayana, S. and Y. Sato, "Heat flux manipulation with engineered thermal materials," Phys. Rev. Lett., Vol. 108, No. 21, 214303, May 2012.

243. Narayana, S., S. Savo, and Y. Sato, "Transient heat flux shielding using thermal metamaterials," Applied Physics Letters, Vol. 102, No. 20, 201904, May 2013.

244. Dede, E. M., T. Nomura, P. Schmalenberg, and J. S. Lee, "Heat flux cloaking, focusing, and reversal in ultra-thin composites considering conduction-convection effects," Applied Physics Letters, Vol. 103, No. 6, 063501, Aug. 2013.

245. Hin Ooi, E. and V. Popov, "Transformation thermodynamics for heat flux management based on segmented thermal cloaks," The European Physical Journal Applied Physics, Vol. 63, No. 1, 10903, Jul. 2013.

246. Schittny, R., M. Kadic, S. Guenneau, and M. Wegener, "Experiments on transformation thermodynamics: Molding the flow of heat," Phys. Rev. Lett., Vol. 110, No. 19, 195901, May 2013.

247. Leonhardt, U., "Applied physics: Cloaking of heat," Nature, Vol. 498, No. 7455, 440-441, Jun. 2013.

248. Xu, H., X. Shi, F. Gao, H. Sun, and B. Zhang, "Ultrathin three-dimensional thermal cloak," Phys. Rev. Lett., Vol. 112, No. 5, 054301, Feb. 2014.

249. Alu, A., "Thermal cloaks get hot," Physics, Vol. 7, No. 12 (3 pages), Feb. 3, 2014.

250. Han, T., X. Bai, D. Gao, J. T. L. Thong, B. Li, and C.-W. Qiu, "Experimental demonstration of a bilayer thermal cloak," Phys. Rev. Lett., Vol. 112, No. 5, 054302, Feb. 2014.

251. Zhang, S., D. A. Genov, C. Sun, and X. Zhang, "Cloaking of matter waves," Phys. Rev. Lett., Vol. 100, No. 12, 123002, Mar. 2008.

252. Greenleaf, A., Y. Kurylev, M. Lassas, and G. Uhlmann, "Approximate quantum cloaking and almost-trapped states," Phys. Rev. Lett., Vol. 101, No. 22, 220404, Nov. 2008.

253. Lin, D.-H., "Cloaking spin-1/2 matter waves," Phys. Rev. A, Vol. 81, No. 6, 063640, Jun. 2010.

254. Lin, D.-H., "Cloaking two-dimensional fermions," Phys. Rev. A, Vol. 84, No. 3, 033624, 2011.

255. Lin, D.-H. and P.-G. Luan, "Cloaking matter waves around a Dirac monopole," Physics Letters A, Vol. 376, No. 5, 675-678, Jan. 2012.

256. Fleury, R. and A. Alu, "Quantum cloaking based on scattering cancellation," Phys. Rev. B, Vol. 87, No. 4, 045423, Jan. 2013.

257. Liao, B., M. Zebarjadi, K. Esfarjani, and G. Chen, "Cloaking core-shell nanoparticles from conducting electrons in solids," Phys. Rev. Lett., Vol. 109, No. 12, 126806, 2012.

258. Fleury, R. and A. Alu, "Furtive quantum sensing using matter-wave cloaks," Phys. Rev. B, Vol. 87, No. 20, 201106, May 2013.

259. Greenleaf, A., A., Y. Kurylev, M. Lassas, U. Leonhardt, and G. Uhlmann, "Cloaked electromagnetic, acoustic, and quantum amplifiers via transformation optics," PNAS, Vol. 109, No. 26, 10169-10174, Jun. 2012.

260. Liao, B., M. Zebarjadi, K. Esfarjani, and G. Chen, "Isotropic and energy-selective electron cloaks on graphene," Phys. Rev. B, Vol. 88, No. 15, 155432, Oct. 2013.

261. Fleury, R. and A. Alu, "Exotic properties and potential applications of quantum metamaterials," Appl. Phys. A, Vol. 109, No. 4, 781-788, Dec. 2012.

262. Silveirinha, M. G. and N. Engheta, "Effective medium approach to electron waves: Graphene superlattices," Phys. Rev. B, Vol. 85, No. 19, 195413, May 2012.

263. Silveirinha, M. G. and N. Engheta, "Transformation electronics: Tailoring the effective mass of electrons," Phys. Rev. B, Vol. 86, No. 16, 161104, Oct. 2012.

264. Silveirinha, M. G. and N. Engheta, "Metamaterial-inspired model for electron waves in bulk semiconductors," Phys. Rev. B, Vol. 86, No. 24, 245302, Dec. 2012.

265. Chen, H., J. Yang, J. Zi, and C. T. Chan, "Transformation media for linear liquid surface waves," EPL, Vol. 85, No. 2, 24004, Jan. 2009.

266. Farhat, M., S. Enoch, S. Guenneau, and A. B. Movchan, "Broadband cylindrical acoustic cloak for linear surface waves in a fluid," Phys. Rev. Lett., Vol. 101, No. 13, 134501, Sep. 2008.

267. Harrington, R. F., "Theory of loaded scatterers," Proc. IEEE, Vol. 3, No. 4, 617-623, Apr. 1964.

268. Schindler, J. K., R. B. Mack, and P. Blacksmith, "The control of electromagnetic scattering by impedance loading," Proc. IEEE, Vol. 53, No. 8, 993-1004, Aug. 1965.

269. Green, R. B., "Scattering from conjugate-matched antennas," IEEE Trans. Antennas Prop., Vol. 14, No. 1, 17-21, Jan. 1966.

270. Hansen, R. C., "Relationships between antennas as scatters and as radiators," Proc. IEEE, Vol. 77, No. 5, 659-662, May 1989.

271. Andersen, J. B. and A. Frandsen, "Absorption efficiency of receiving antennas," IEEE Trans. Antennas Prop., Vol. 53, No. 9, 2843-2849, Sep. 2005.

272. Kwon, D. H. and D. M. Pozar, "Optimal characteristics of an arbitrary receive antenna," IEEE Trans. Antennas Prop., Vol. 57, No. 12, 3720-3727, Dec. 2009.

273. Kwon, D. H. and D. M. Pozar, "Design of received and scattered powers for dipole arrays using load optimization," 2010 IEEE Antennas and Propagation Society International Symposium (APSURSI), Jul. 2010.

274. Karilainen, A. O. and S. A. Tretyakov, "Circularly polarized receiving antenna incorporating two helices to achieve low backscattering," IEEE Trans. Antennas Prop., Vol. 60, No. 7, 3471-3475, Jul. 2012.

275. Alu, A. and N. Engheta, "Cloaking a sensor," Phys. Rev. Lett., Vol. 102, 233901, Jun. 2009.

276. Alu, A. and N. Engheta, "Cloaking a receiving antenna or a sensor with plasmonic metamaterials," Metamaterials, Vol. 4, No. 4, 153-159, Mar. 2010.

277. Alu, A. and S. Maslovski, "Power relations and a consistent analytical model for receiving wire antennas," IEEE Trans. Antennas Prop., Vol. 58, No. 5, 1436-1448, May 2010.

278. Soric, J. C., R. Fleury, A. Monti, A. Toscano, F. Bilotti, and A. Alu, "Controlling scattering and absorption with metamaterial covers," IEEE Trans. Antennas Prop., Vol. 62, No. 8, 4220-4229, Jul. 2014.

279. Kwon, D. H. and D. H. Werner, "Restoration of antenna parameters in scattering environments using electromagnetic cloaking," Appl. Phys. Lett., Vol. 92, No. 11, 113507, Mar. 2008.

280. Monti, A., A. Toscano, and F. Bilotti, "Metasurface mantle cloak for antenna applications," 2012 IEEE Antennas and Propagation Society International Symposium (APSURSI), Jul. 2012.

281. Valagiannopoulos, C. A. and N. L. Tsitsas, "Integral equation analysis of a low-profile receiving planar microstrip antenna with a cloaking substrate," Radio Sci., Vol. 47, RS004878, Apr. 2012.

282. Vehmas, J., P. Alitalo, and S. Tretyakov, "Experimental demonstration of antenna blockage reduction with a transmission-line cloak," IET Microw. Antennas Propag., Vol. 6, No. 7, 830-834, Jan. 2012.

283. Monti, A., J. Soric, A. Alu, F. Bilotti, A. Toscano, and L. Vegni, "Overcoming mutual blockage between neighboring dipole antennas using a low-profile patterned metasurface," IEEE Antennas and Wireless Propagation Letters, Vol. 11, 1414, 2012.

284. Alu, A. and N. Engheta, "Cloaked near-field scanning optical microscope tip for noninvasive near-field imaging," Phys. Rev. Lett., Vol. 105, No. 26, 263906, Dec. 2010.

285. Bilotti, F., S. Tricarico, F. Pierini, and L. Vegni, "Cloaking apertureless near-field scanning optical microscopy tips," Optics Lett., Vol. 36, No. 26, 211-213, Jan. 2011.

286. Fan, P., U. K. Chettiar, L. Cao, F. Afshinmanesh, N. Engheta, and M. L. Brongersma, "An invisible metal-semiconductor photodetector," Nature Photonics, Vol. 8, 380-385, May 2012.

287. Fleury, R., J. Soric, and A. Alu, "Physical bounds on absorption and scattering for cloaked sensors," Phys. Rev. B, Vol. 89, No. 4, 045122, 12 pages, Jan. 15, 2014.

288. Alu, A. and N. Engheta, "How does zero forward-scattering in magnetodielectric nanoparticles comply with the optical theorem?," J. Nanophoton., Vol. 4, No. 1, 041590, May 2010.

289. Zhang, B., 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., Vol. 100, 063904, Feb. 2008.

290. Xu, T., X. F. Zhu, B. Liang, Y. Li, X. Y. Zou, and J. C. Cheng, "Scattering reduction for an acoustic sensor using a multilayer shell comprising a pair of homogenous isotropic single-negative media," Appl. Phys. Lett., Vol. 101, 033509, Jul. 2012.