Monolithic Forward-Looking Photodetector for Use as Ultra-Compact Wavemeter with Wide Spectral Range

摘要

A monolithic, forward-looking photodetector that can be used as a wavemeteris proposed. The device consists of two vertically stacked photosensitivelayers that can be read out separately. The top photodetector contains avertical gradient of semiconductor alloy composition, leading to a designed,broad, ideally linearly increasing absorption edge. The bottom photodetectoris sensitive to all wavelengths falling into the device. The ratio of the twophotosignals is related to the wavelength of monochromatic incomingradiation. The spectral range of the device is determined by the used alloycompositions. The device response for the (Mg,Zn)O material system withsensitivity in the ultraviolet spectral range is simulated.