Transient photoresponse and incident power dependence of high-efficiency germanium quantum dot photodetectors

Abstract

We report a systematic study of time-resolved and power-dependent photoresponse in high-efficiency germanium quantum dot photodetectors (Ge-QD PDs), with internal quantum efficiencies greater than 100 over a broad wavelength, reverse bias, and incident power range. Turn-on and turn-off response times (τ on and τ off) are shown to depend on series resistance, bias, optical power, and thickness (W QD) of the Ge-QD layer, with measured τ off values down to ∼40 ns. Two different photoconduction regimes are observed at low and high reverse bias, with a transition around -3 V. A transient current overshoot phenomenon is also observed, which depends on bias and illumination power. © 2012 American Institute of Physics

Perovskite/Organic Bulk‐Heterojunction Integrated Ultrasensitive Broadband Photodetectors with High Near‐Infrared External Quantum Efficiency over 70%

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A Flexible UV–Vis–NIR Photodetector based on a Perovskite/Conjugated‐Polymer Composite

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Low‐Temperature Operation of High‐Efficiency Germanium Quantum Dot Photodetectors in the Visible and Near Infrared

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