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arXiv · 2205.01720

Quadrupolar photovoltaic effect in the terahertz range in a two-dimensional spin-3/2 hole system

Mohsen Farokhnezhad·W. A. Coish·Reza Asgari·Dimitrie Culcer
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Abstract

We identify a strong photovoltaic response due to the non-linear optical transition between heavy and light hole sub-bands enabled by T_d-symmetry in a quantum well, which we term the quadrupolar photovoltaic effect (QPE). The photovoltaic current exhibits a strong resonance in the vicinity of the heavy hole-light hole splitting, with a magnitude governed by the momentum relaxation time, which can reach nanoseconds in GaAs holes. Since the heavy hole-light hole splitting can be tuned from a few meV to nearly 100 meV the QPE could serve as the basis for a terahertz photo-detector. We discuss strategies for experimental observation and device applications.

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Mohsen Farokhnezhad, W. A. Coish, Reza Asgari, Dimitrie Culcer. 2022-05-03. Quadrupolar photovoltaic effect in the terahertz range in a two-dimensional spin-3/2 hole system. https://doi.org/10.1103/physrevb.107.085405

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