We demonstrate that homogeneous naturally-occurring materials can form hyperbolic media, and can be used for nonmagnetic negative refractive index systems. We present specific realizations of the proposed approach for the THz and far-IR frequencies. The proposed structures operate away from resonance, thereby promising the capacity for low-loss devices. Following the initial proposal by Veselago in 1968 [1], negative refraction materials spent over 30 years as a forlorn curiosity before being resurrected with renewed interest from both theoretical and experimental groups. Within the last decade it was realized that these materials (known also as left-handed materials), along with a broader classes of exotic media (known as epsilon near-zero materials, hyperbolic materials, etc.) possess unusual properties, some of which were not recognized at the time of their conceptions [2]. These properties include resonant enhancement of evanescent fields, strong suppression of diffraction, unusual modification to optical density of states, potentially enabling near-perfect imaging below the diffraction limit, and leading to a new class of optical devices [3], as well as nontrivial behavior in the nonlinear regime [4]. Despite initial controversy over the realizability of negative index materials (NIMs), successful proof of principle demonstrations have been accomplished [3, 5–8]. Existing designs for left-handed materials rely on achieving overlapping dipolar and magnetic resonances in subwavelength composites (metamaterials) [9, 10], or using photonic crystals near the bandgap [3, 11]. Both of these approaches necessitate complicated 3D patterning of the medium with microstructured periodic arrays. Fabrication of such structures presents significant challenges even for GHz applications, while manufacturing metamaterials for higher frequencies becomes harder still [12]. Furthermore, near-resonant operational losses impose severe limitations on the imaging resolution [13]. As an alternative to periodic systems, a waveguide-based implementation of a NIM was proposed [14], which obviates the need for negative magnetic permeability and does not require periodic patterning. This approach circumvents major manufacturing obstacles to achieving NIM behavior at terahertz or optical frequencies, and simultaneously opens a new avenue in imaging, sensing, and light emission applications [15, 16] To achieve this behavior, the waveguide material must possess characteristics of a uniaxial medium with a significant anisotropy. Furthermore, this anisotropy must ensure that (the
References
[1]
V. G. Veselago, “The electrodynamics of substances with simultaneously negative values of ε and μ,” Soviet Physics Uspekhi, vol. 10, no. 4, article 509, 1968.
[2]
M. Noginov and V. A. Podolskiy, Eds., Tutorials in Metamaterials, Taylor & Francis, Boca Raton, Fla, USA, 2012.
[3]
P. V. Parimi, W. T. Lu, P. Vodo, and S. Sridhar, “Imaging by flat lens using negative refraction,” Nature, vol. 426, no. 6965, article 404, 2003.
[4]
I. R. Gabitov, R. A. Indik, N. M. Litchinitser, A. I. Maimistov, V. M. Shalaev, and J. E. Soneson, “Double-resonant optical materials with embedded metal nanostructures,” Journal of the Optical Society of America B, vol. 23, no. 3, pp. 535–542, 2006.
[5]
R. A. Shelby, D. R. Smith, and S. Schultz, “Experimental verification of a negative index of refraction,” Science, vol. 292, no. 5514, pp. 77–79, 2001.
[6]
V. M. Shalaev, W. Cai, U. K. Chettiar et al., “Negative index of refraction in optical metamaterials,” Optics Letters, vol. 30, no. 24, pp. 3356–3358, 2005.
[7]
E. Schonbrun, T. Yamashita, W. Park, and C. J. Summerss, “Negative-index imaging by an index-matched photonic crystal slab,” Physical Review B, vol. 73, no. 19, Article ID 195117, 6 pages, 2006.
[8]
G. Dolling, C. Enkrich, M. Wegener, C. M. Soukoulis, and S. Linden, “Simultaneous negative phase and group velocity of light in a metamaterial,” Science, vol. 312, no. 5775, pp. 892–894, 2006.
[9]
D. R. Smith, W. J. Padilla, D. C. Vier, S. C. Nemat-Nasser, and S. Shultz, “Composite medium with simultaneously negative permeability and permittivity,” Physical Review Letters, vol. 84, no. 18, pp. 4184–4187, 2000.
[10]
C. G. Parazzoli, R. B. Greegor, K. Li, B. E. C. Koltenbah, and M. Tanielian, “Experimental verification and simulation of negative index of refraction using Snell's law,” Physical Review Letters, vol. 90, no. 10, Article ID 107401, 4 pages, 2003.
[11]
M. Notomi, “Theory of light propagation in strongly modulated photonic crystals: refractionlike behavior in the vicinity of the photonic band gap,” Physical Review B, vol. 62, no. 16, pp. 10696–10705, 2000.
[12]
A. Boltasseva, “Fabrication of optical metamaterials,” in Tutorials in Metamaterials, M. Noginov and V. A. Podolskiy, Eds., Taylor & Francis, Boca Raton, Fla, USA, 2012.
[13]
V. A. Podolskiy and E. E. Narimanov, “Near-sighted superlens,” Optics Letters, vol. 30, no. 1, pp. 75–77, 2005.
[14]
V. A. Podolskiy and E. E. Narimanov, “Strongly anisotropic waveguide as a nonmagnetic left-handed system,” Physical Review B, vol. 71, no. 20, Article ID 201101(R), 4 pages, 2005.
[15]
V. A. Podolskiy, “Hyperbolic metamaterials,” in Tutorials in Metamaterials, M. Noginov and V. A. Podolskiy, Eds., Taylor & Francis, Boca Raton, Fla, USA, 2012.
[16]
L. V. Alekseyev and E. E. Narimanov, “Radiative decay engineering in metamaterials,” in Tutorials in Metamaterials, M. Noginov and V. A. Podolskiy, Eds., Taylor & Francis, Boca Raton, Fla, USA, 2012.
[17]
Z. Jacob, L. V. Alekseyev, and E. Narimanov, “Optical hyperlens: far-field imaging beyond the diffraction limit,” Optics Express, vol. 14, no. 18, pp. 8247–8256, 2006.
[18]
S. Thongrattanasiri and V. A. Podolskiy, “Hypergratings: nanophotonics in planar anisotropic metamaterials,” Optics Letters, vol. 34, no. 7, pp. 890–892, 2009.
[19]
A. Salandrino and N. Engheta, “Far-field subdiffraction optical microscopy using metamaterial crystals: theory and simulations,” Physical Review B, vol. 74, no. 7, Article ID 075103, 2006.
[20]
Z. Liu, H. Lee, Y. Xiong, C. Sun, and X. Zhang, “Far-field optical hyperlens magnifying sub-diffraction-limited objects,” Science, vol. 315, no. 5819, article 1686, 2007.
[21]
H. N. S. Krishnamoorthy, Z. Jacob, E. Narimanov, I. Kretzschmar, and V. M. Menon, “Topological transitions in metamaterials,” Science, vol. 336, no. 6078, pp. 205–209, 2012.
[22]
E. E. Narimanov, H. Li, Y. A. Barnakov, and M. A. Noginov, “Darker than black: radiation-absorbing metamaterial,” in Proceedings of the Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference: 2010 Laser Science to Photonic Applications (CLEO/QELS'10), Optical Society of America, San Jose, Calif, USA, May 2010, presentation #QPDA6.
[23]
P. Evans, W. R. Hendren, R. Atkinson et al., “Growth and properties of gold and nickel nanorods in thin film alumina,” Nanotechnology, vol. 17, no. 23, pp. 5746–5753, 2006.
[24]
J. Yao, Z. Liu, Y. Liu et al., “Optical negative refraction in bulk metamaterials of nanowires,” Science, vol. 321, no. 5891, p. 930, 2008.
[25]
A. J. Hoffman, L. Alekseyev, S. S. Howard et al., “Negative refraction in semiconductor metamaterials,” Nature Materials, vol. 6, no. 12, pp. 946–950, 2007.
[26]
J. Sun, J. Zhou, B. Li, and F. Kang, “Indefinite permittivity and negative refraction in natural material: graphite,” Applied Physics Letters, vol. 98, no. 10, Article ID 101901, 3 pages, 2011.
[27]
R. Wangberg, J. Elser, E. E. Narimanov, and V. A. Podolskiy, “Nonmagnetic nanocomposites for optical and infrared negative-refractive-index media,” Journal of the Optical Society of America B, vol. 23, no. 3, pp. 498–505, 2006.
[28]
C. Luo, S. G. Johnson, and J. D. Joannopoulos, “All-angle negative refraction without negative effective index,” Physical Review B, vol. 65, no. 20, Article ID 201104(R), 4 pages, 2002.
[29]
A. Hadni and X. Gerbaux, “Far IR excitation of longitudinal optical phonons in triglycine sulphate,” Ferroelectrics, vol. 248, no. 1, pp. 15–26, 2000.
[30]
X. Gerbaux, M. Tazawa, and A. Hadni, “Far IR transmission measurements on triglycine sulphate (TGS), at 5K,” Ferroelectrics, vol. 215, no. 1, pp. 47–63, 1998.
[31]
T. Dumelow, J. A. P. da Costa, and V. N. Freire, “Slab lenses from simple anisotropic media,” Physical Review B, vol. 72, no. 23, Article ID 235115, 8 pages, 2005.
[32]
M. Schubert, T. E. Tiwald, and C. M. Herzinger, “Infrared dielectric anisotropy and phonon modes of sapphire,” Physical Review B, vol. 61, no. 12, pp. 8187–8201, 2000.
[33]
W. S. Boyle, A. D. Brailsford, and J. K. Galt, “Dielectric anomalies and cyclotron absorption in the infrared: observations on bismuth,” Physics Reviews, vol. 109, no. 4, pp. 1396–1398, 1958.
[34]
W. S. Boyle and A. D. Brailsford, “Far infrared studies of bismuth,” Physics Reviews, vol. 120, no. 6, pp. 1943–1949, 1960.
[35]
V. D. Kulakovskii and V. D. Egorov, “Plasma reflection in bismuth and bismuth-antimony alloys,” Soviet Physics—Solid State, vol. 15, no. 7, p. 1368, 1974.
[36]
V. S. Edelman, “Electrons in bismuth,” Advances in Physics, vol. 25, no. 6, pp. 555–613, 1976.
[37]
F. Y. Yang, K. Liu, K. Hong, D. H. Reich, P. C. Searson, and C. L. Chien, “Large magnetoresistance of electrodeposited single-crystal bismuth thin films,” Science, vol. 284, no. 5418, pp. 1335–1337, 1999.
[38]
E. Gerlach, P. Grosse, M. Rautenberg, and W. Senske, “Dynamical conductivity and plasmon excitation in Bi,” Physica Status Solidi (b), vol. 75, no. 2, pp. 553–558, 1976.
[39]
A. A. Govyadinov and V. A. Podolskiy, “Metamaterial photonic funnels for subdiffraction light compression and propagation,” Physical Review B, vol. 73, no. 15, Article ID 155108, 5 pages, 2006.
