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arXiv · 2210.02839

Current-induced enhancement of photo-response in graphene THz radiation detectors

K. Indykiewicz·C. Bray·C. Consejo·F. Teppe·S. Danilov·S. D. Ganichev·A. Yurgens
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Abstract

Thermoelectric readout in a graphene THz radiation detector requires a p-n junction across the graphene channel. Even without an intentional p-n junction, two latent junctions can exist in the vicinity of the electrodes/antennas through the proximity to metal. In a symmetrical structure, these junctions are connected back-to-back and therefore counterbalance each other with regard to rectification of the ac signal. Because of the Peltier effect, a small dc current results in additional heating in one- and cooling in another p-n junction, thereby breaking the symmetry. The p-n junctions then no longer cancel, resulting in a greatly enhanced rectified signal. This allows to simplify the design and effectively control the sensitivity of the THz-radiation detectors.

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K. Indykiewicz, C. Bray, C. Consejo, F. Teppe, S. Danilov, S. D. Ganichev, A. Yurgens. 2022-10-06. Current-induced enhancement of photo-response in graphene THz radiation detectors. https://doi.org/10.1063/5.0117818

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