Search results for "Photoconduction"
showing 2 items of 2 documents
High-Efficiency Multi-Junction Photovoltaic Cells in School Physics Laboratory
2020
Energy consumption in the world is increasing more and more due to the huge energy request coming from emerging countries such as China, India, etc. To face the challenge of sustainability, a solution may be the use of solar energy, since it is the most abundant renewable energy source on Earth. The electromagnetic energy coming from the Sun can be converted into usable energy (electricity) by solar cells, whose conversion efficiency is continuously increasing due to scientific and technological progress. The proposed activity is thought to be carried out with secondary as well as high school students to allow teachers to discuss sustainability issues, and to provide students with an introd…
Transient photoresponse and incident power dependence of high-efficiency germanium quantum dot photodetectors
2012
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 …