Group-Velocity Anomaly Modes in Hybrid Bands of Photonic Crystals Made of Ferroelectrics

Abstract:

In photonic crystals composed of ferroelectrics, the hybrid bands with corresponding to new additional band gaps are expected to appear around the Brillouin zone’s center and boundaries. In this hybrid bands, the group-velocity anomaly modes related to the phonon-polariton branches are expected to be discovered. Propagation characteristics of the group-velocity anomaly modes in the hybrid bands of one-dimensional photonic crystals fabricated by ferroelectric Li₂Ge₇O₁₅ single crystals are discussed on the basis of finite element method and finite-difference time-domain numerical analyses and experimental results obtained by terahertz time-domain spectroscopy. It is founded that the electric-field intensity of the standing-wave mode at the end point of the dielectric band branch is found to be localized around all of the ferroelectrics plates in the photonic crystal. In contrast, group-velocity anomaly mode in the vicinity of the standing-wave mode is strongly localized around the first ferroelectrics plate on the incident side and decays as it propagates through the following ferroelectrics plates.

• Periodical: Advances in Science and Technology (Volume 98)
• Pages: 109-114
• DOI: https://doi.org/10.4028/www.scientific.net/AST.98.109
• Online since: October 2016
• Authors: Mitsuo Wada Takeda, Akihiko Arikawa, Ryohei Araki, Yosuke Nakata, Fumiaki Miyamaru, Toshihisa Yamaguchi
• Keywords: Ferroelectrics, Phonon-Polariton, Photon Localization, Photonic Crystals, THz-TDS

References

[1] K. Ohtaka, Energy band of photons and low-energy photon diffraction, Phys. Rev. B 19 (1979) 5057–5067.

DOI: 10.1103/physrevb.19.5057

[2] E. Yablonovich, Inhibited spontaneous emission in solid-state physics and electronics, Phys. Rev. Lett. 58 (1987) 2059–(2062).

DOI: 10.1103/physrevlett.58.2059

[3] Special review issues on photonic band-gap structures: C.W. Bowden, J.P. Dowling, H.O. Everitt, J. Opt. Soc. Am. B 10 (1993); G. Kurizki, J.W. Haus, J. Mod. Opt. 41 (1994).

[4] M. Wada, Y. Doi, K. Inoue, J. W. Haus, Z. Yuan, A simple-cubic photonic lattice in silicon, Appl. Phys. Lett. 70 (1997) 2966.

DOI: 10.1063/1.118758

[5] M. Wada, Y. Doi, K. Inoue, J. W. Haus, Far-infrared transmittance and band-structure correspondence in two-dimensional air-rod photonic crystals, Phys. Rev. B 55 (1997) 10443–10450.

DOI: 10.1103/physrevb.55.10443

[6] T. Aoki, M. W. Takeda, J. W. Haus, Z. Yuan, M. Tani, K. Sakai, N. Kawai, K. Inoue, Terahertz time-domain study of a pseudo-simple cubic photonic lattice, Phys. Rev. B 64 (2001) 045106.

DOI: 10.1103/physrevb.64.045106

[7] M. Iida, M. Tani, K. Sakai, M. Watanabe, S. Katayama, H. Kondo, H. Kitahara, S. Kato, M. W. Takeda, Emission from planar defect modes excited with surface modes in three-dimensional photonic crystals, Phys. Rev. B 69 (2004) 245119.

DOI: 10.1103/physrevb.69.245119

[8] M. Born, K. Huang, Dynamical Theory of Crystal Lattices, Oxford University Press, Oxford, (1954).

[9] T. Kurosawa, Polarization waves in solids, J. Phys. Soc. Jpn. 16 (1961) 1298–1308.

[10] S. Kojima, N. Tsumura, M. W. Takeda, S. Nishizawa, Far-infrared phonon-polariton dispersion probed by terahertz time-domain spectroscopy, Phys. Rev. B 67 (2003) 035102.

DOI: 10.1103/physrevb.67.035102

[11] K. C. Huang, P. Bienstman, J. D. Joannopoulos, K. A. Nelson, S. Fan, Phonon-polariton excitations in photonic crystals, Phys. Rev. B 68 (2003) 075209.

DOI: 10.1103/physrevb.69.159903

[12] P. T. Lin, A. Imre, L. E. Ocola, B. W. Wessels, Thin film ferroelectric photonic crystals and their application to thermo-optic switches, Opt. Commun. 282 (2009) 3364–3367.

DOI: 10.1016/j.optcom.2009.03.063

[13] M. Hangyo, M. Tani, T. Nagashima, Terahertz time-domain spectroscopy of solids: A review, Int. J. Infrared Millimeter Waves 26 (2005) 1661–1690.

DOI: 10.1007/s10762-005-0288-1

[14] M. Wada, A. Sawada, Y. Ishibashi, Ferroelectricity and a soft mode in Li2Ge7O15 crystal, J. Phys. Soc. Jpn. 50 (1981) 1811–1812.

DOI: 10.1143/jpsj.50.1811

[15] M. Wada, Y. Ishibashi, Ferroelectric phase transition in Li2Ge7O15, J. Phys. Soc. Jpn. 52 (1983) 193–199.

[16] M. W. Takeda, Y. Noda, T. Yamaguchi, Inelastic neutron scattering study of ferroelectric phase transition in lithium heptagermanate (Li2Ge7O15), Ferroelectrics 412 (2011) 45–47.

DOI: 10.1080/00150193.2011.542695