15 April 1997 Nonlinear photoresponse of quantum well infrared photodetectors at high-excitation power
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Nonlinear photoresponse effects at high excitation power in quantum well infrared photodetectors (QWIPs) are studied both experimentally and theoretically. The photoconductivity nonlinearity is mainly caused by a redistribution of the electric potential at high power, which leads to a decrease of electric field in the bulk of the QWIP. As a result of the decreased field, the photoexcited electron escape probability and drift velocity decrease, resulting in a decrease of responsivity. These effects are strongly influenced by QWIP structural parameters and operating conditions. In QWIPs with a few QWs the IR power required to observe a decrease of responsivity is much lower than that needed to cause the saturation of the intersubband absorption. Key factors in designing a QWIP with a suppressed nonlinearity are discussed.
© (1997) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Maxim Ershov, Maxim Ershov, Hui Chun Liu, Hui Chun Liu, Margaret Buchanan, Margaret Buchanan, Zbigniew R. Wasilewski, Zbigniew R. Wasilewski, "Nonlinear photoresponse of quantum well infrared photodetectors at high-excitation power", Proc. SPIE 2999, Photodetectors: Materials and Devices II, (15 April 1997); doi: 10.1117/12.271210; https://doi.org/10.1117/12.271210

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