Infrared laser detection by antenna‐coupled point‐contact schottky diodes

Abstract

The responsivity of antenna‐coupled point‐contact Schottky diodes to CO2 laser radiation was studied experimentally. the very clear antenna‐pattern was obtained for the 10.6 μm radiation and agreed with theory based on the traveling wave antenna. the bias voltage dependence of the detected voltage agreed with the results calculated by using measured dI/dV ‐ V and d2I/dV2 ‐ V characteristics. It is seen from this that the fabricated devices respond to the frequency of a CO2 laser as a square‐law detector (resulting from nonlinearity of the I ‐ V characteristic at CO2 laser frequency) and detect the laser signal by rectification due to the nonlinear current‐voltage characteristic.