Temperature dependence of current–voltage characteristics of terahertz quantum-well photodetectors

We have performed current–voltage (I–V) measurements on a terahertz quantum-well photodetector (QWP) at different temperatures and employed an emission-capture model to simulate the I–V curves. A temperature-dependent vertical electron drift mobility has been used to fit the curves from 7 K to 20 K. Photocurrents caused by 300 K background radiation have also been measured at different temperatures and a background-limited infrared performance (blip) temperature of 12 K for this terahertz detector has been determined. The current–temperature (I–T) curves derived from the measured dark I–V curves indicate that the thermionic emission process is the major mechanism for dark current in this terahertz detector.