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arXiv · 1112.5654

Shockley-Ramo theorem and long-range photocurrent response in gapless materials

Justin C. W. Song·Leonid S. Levitov
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Abstract

Scanning photocurrent maps of gapless materials, such as graphene, often exhibit complex patterns of hot spots positioned far from current-collecting contacts. We develop a general framework that helps to explain the unusual features of the observed patterns, such as the directional effect and the global character of photoresponse. We show that such a response is captured by a simple Shockley-Ramo-type approach. We examine specific examples and show that the photoresponse patterns can serve as a powerful tool to extract information about symmetry breaking, inhomogeneity, chirality, and other local characteristics of the system.

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Justin C. W. Song, Leonid S. Levitov. 2015-01-03. Shockley-Ramo theorem and long-range photocurrent response in gapless materials. https://doi.org/10.1103/physrevb.90.075415

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