Magnetotransport in quantum cascade detectors: analyzing the current under illumination

Laboratoire Pierre Aigrain, Ecole Normale Supérieure CNRS (UMR 8551), 24 rue Lhomond, 75231 Paris Cedex 05, France. .
Nanoscale Research Letters (Impact Factor: 2.78). 03/2011; 6(1):206. DOI: 10.1186/1556-276X-6-206
Source: PubMed


Photocurrent measurements have been performed on a quantum cascade detector structure under strong magnetic field applied parallel to the growth axis. The photocurrent shows oscillations as a function of B. In order to describe that behavior, we have developed a rate equation model. The interpretation of the experimental data supports the idea that an elastic scattering contribution plays a central role in the behavior of those structures. We present a calculation of electron lifetime versus magnetic field which suggests that impurities scattering in the active region is the limiting factor. These experiments lead to a better understanding of these complex structures and give key parameters to optimize them further.

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Available from: Francesca Carosella, Oct 04, 2015
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