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arXiv · 1705.11006

Gapless surface states originated from accidentally degenerate quadratic band touching in a three-dimensional tetragonal photonic crystal

Tetsuyuki Ochiai
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Abstract

A tetragonal photonic crystal composed of high-index pillars can exhibit a frequency-isolated accidental degeneracy at a high-symmetry point in the first Brillouin zone. A photonic band gap can be formed there by introducing a geometrical anisotropy in the pillars. In this gap, gapless surface/domain-wall states emerge under a certain condition. We analyze their physical property in terms of an effective hamiltonian, and a good agreement between the effective theory and numerical calculation is obtained.

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Tetsuyuki Ochiai. 2017-05-31. Gapless surface states originated from accidentally degenerate quadratic band touching in a three-dimensional tetragonal photonic crystal. https://doi.org/10.1103/physreva.96.043842

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