Wavelength Tuning of Type-II Superlattice Spectral Response Using a Square Coaxial Aperture Array

We present the design and fabrication results for wavelength tuning of InAs/GaSb type-II superlattice spectral response based on square coaxial aperture array at mid-wave infrared. This structure is designed as a wavelength adjustable filter with different parameters in the 2 – 6 μm. Its spectrum does not depend on the angle of the incident light and has a Gaussian shape. There was a slight difference in the designed parameters due to imperfection fabrication, but the trend of the spectrum according to the difference was confirmed and analyzed by simulation. The spectral responsivity of the device was measured, and wavelength tuning was observed.