Effects of hydrostatic pressure on an L1 and L3 cavity of a photonic slab

In this work, we used the guided-mode expansion method to calculate the photonic band dispersion in two-dimensional photonic crystal slabs. The photonic lattice is hexagonal, composed of air holes with a circular cross-section. The slab is made of a semiconductor material (GaAs) with a dielectric function dependent on pressure and temperature. By maintaining the constant temperature, we found a shift in the photonic band dispersion towards regions of larger frequencies when the hydrostatic pressure increased. Moreover, we consider the effects of pressure on defective modes in cavities L1 and L3. The results reveal that by increasing the pressure, the position of the defective modes manages to tune for the photonic gap. Additionally, we found a decrease in the Q-factor for the L1 cavity when the pressure increases. However, for the L3 cavity, the Q-factor exhibits a non-monotonous behavior by increasing the pressure.