Thermo-optic effect on the photonic band structure in a two-dimensional square lattice photonic crystal

Abstract

In this study, the standard plane wave expansion method is used to determine the effects of temperature variation on the photonic band structure in a two-dimensional square lattice photonic crystal composed of GaAs cylinders with circular cross sections embedded in air. The photonic band structure shifts toward short-frequency regions due to thermo-optic effects caused by the increase in temperature and refractive index contrast. The photonic band structure is determined using the supercell technique upon removing two GaAs cylinders from the photonic crystal structure. The photonic band gap also comprises defective bands whose energies increase with increasing temperature. Thus, defective bands are not completely planar due to the radiation escaping into the cavity.