Background-limited terahertz quantum-well photodetector

We report terahertz quantum-well photodetectors with background-limited infrared performance (BLIP). The device dark current characteristics were improved by employing thick barriers to reduce interwell tunneling. BLIP operations were observed for all samples (three in total) designed for different wavelengths. BLIP temperatures of 17, 13, and 12 K were achieved for peak detection frequencies at 9.7 THz (31 mu m), 5.4 THz (56 mu m), and 3.2 THz (93 mu m), respectively. (c) 2005 American Institute of Physics.