Demonstration of a three-dimensional simple-cubic infrared photonic crystal

This letter reports on the use of nonselective dry and selective wet etching to fabricate a gallium arsenide (GaAs) based three-dimensional infrared photonic crystal with a simple-cubic lattice structure. A two-and-one-half-period photonic crystal fabricated using this procedure demonstrated a drop in transmission of approximately 10 dB at a center wavelength of 12 μm for normally incident angles. A shift in the long-wavelength shoulder from 16 to 15 μm was observed as the incident infrared beam was varied from normal to oblique incidence. The measured drop in transmission agrees well with the band gap predicted theoretically for this simple-cubic structure.