Antenna structures for optical coupling in quantum-well infrared detectors

Predicted performance for antenna-coupled quantum-well infrared photodetectors (QWIPs) is presented. These structures contain a patterned metal antenna layer and dielectric backplane reflector in place of the usual metal phase grating. When illuminated by normally incident plane-wave illumination, the antenna structures generate both evanescent and propagating modes that have the required polarization to be absorbed by the aw stack. An undersampled spectral technique is also demonstrated for using the finite-difference, time-domain (FDTD) technique to compute spectral quantum efficiency in a single FDTD run.