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arXiv · 1904.07815

Photocurrent and photoconductance of an helical edge state

Jonathan Atteia·Jérôme Cayssol
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Abstract

We consider the helical edge state of a Quantum Spin Hall insulator, connected between two leads, and irradiated by a monochromatic and circularly polarized electromagnetic wave. The photocurrent generated within the helical edge state is studied as function of the characteristics of the electromagnetic radiation and electronic doping of the edge state. We focus on the effect of the leads on the photocurrent. We also investigate the photoconductance of the helical edge state in presence of a voltage bias between the leads.

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Jonathan Atteia, Jérôme Cayssol. 2019-04-16. Photocurrent and photoconductance of an helical edge state. https://doi.org/10.1103/physrevb.100.245412

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