Anomalous terahertz photoconductivity caused by the superballistic flow of hydrodynamic electrons in graphene

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kravtsov, M., Shilov, A. L., Yang, Y., Pryadilin, T., Kashchenko, M. A., Popova, O., Titova, M., Voropaev, D., Wang, Y., Shein, K., Gayduchenko, I., Goltsman, G. N., Lukianov, M., Kudriashov, A., Taniguchi, T., Watanabe, K., Svintsov, D. A., Principi, A., Adam, S., Novoselov, K. S., Bandurin, D. A.
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910819430694912
author Kravtsov, M.
Shilov, A. L.
Yang, Y.
Pryadilin, T.
Kashchenko, M. A.
Popova, O.
Titova, M.
Voropaev, D.
Wang, Y.
Shein, K.
Gayduchenko, I.
Goltsman, G. N.
Lukianov, M.
Kudriashov, A.
Taniguchi, T.
Watanabe, K.
Svintsov, D. A.
Principi, A.
Adam, S.
Novoselov, K. S.
Bandurin, D. A.
author_facet Kravtsov, M.
Shilov, A. L.
Yang, Y.
Pryadilin, T.
Kashchenko, M. A.
Popova, O.
Titova, M.
Voropaev, D.
Wang, Y.
Shein, K.
Gayduchenko, I.
Goltsman, G. N.
Lukianov, M.
Kudriashov, A.
Taniguchi, T.
Watanabe, K.
Svintsov, D. A.
Principi, A.
Adam, S.
Novoselov, K. S.
Bandurin, D. A.
contents Light incident upon materials can induce changes in their electrical conductivity, a phenomenon referred to as photoresistance. In semiconductors, the photoresistance is negative, as light-induced promotion of electrons across the band gap enhances the number of charge carriers participating in transport. In superconductors, the photoresistance is positive because of the destruction of the superconducting state, whereas in normal metals it is vanishing. Here we report a qualitative deviation from the standard behavior in metallic graphene. We show that Dirac electrons exposed to continuous wave (CW) terahertz (THz) radiation can be thermally decoupled from the lattice by 50~K which activates hydrodynamic electron transport. In this regime, the resistance of graphene constrictions experiences a decrease caused by the THz-driven superballistic flow of correlated electrons. We analyze the dependencies of the negative photoresistance on the carrier density, and the radiation power and show that our superballistic devices operate as sensitive phonon-cooled bolometers and can thus offer a picosecond-scale response time. Beyond their fundamental implications, our findings underscore the practicality of electron hydrodynamics in designing ultra-fast THz sensors and electron thermometers.
format Preprint
id arxiv_https___arxiv_org_abs_2403_18492
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Anomalous terahertz photoconductivity caused by the superballistic flow of hydrodynamic electrons in graphene
Kravtsov, M.
Shilov, A. L.
Yang, Y.
Pryadilin, T.
Kashchenko, M. A.
Popova, O.
Titova, M.
Voropaev, D.
Wang, Y.
Shein, K.
Gayduchenko, I.
Goltsman, G. N.
Lukianov, M.
Kudriashov, A.
Taniguchi, T.
Watanabe, K.
Svintsov, D. A.
Principi, A.
Adam, S.
Novoselov, K. S.
Bandurin, D. A.
Mesoscale and Nanoscale Physics
Light incident upon materials can induce changes in their electrical conductivity, a phenomenon referred to as photoresistance. In semiconductors, the photoresistance is negative, as light-induced promotion of electrons across the band gap enhances the number of charge carriers participating in transport. In superconductors, the photoresistance is positive because of the destruction of the superconducting state, whereas in normal metals it is vanishing. Here we report a qualitative deviation from the standard behavior in metallic graphene. We show that Dirac electrons exposed to continuous wave (CW) terahertz (THz) radiation can be thermally decoupled from the lattice by 50~K which activates hydrodynamic electron transport. In this regime, the resistance of graphene constrictions experiences a decrease caused by the THz-driven superballistic flow of correlated electrons. We analyze the dependencies of the negative photoresistance on the carrier density, and the radiation power and show that our superballistic devices operate as sensitive phonon-cooled bolometers and can thus offer a picosecond-scale response time. Beyond their fundamental implications, our findings underscore the practicality of electron hydrodynamics in designing ultra-fast THz sensors and electron thermometers.
title Anomalous terahertz photoconductivity caused by the superballistic flow of hydrodynamic electrons in graphene
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2403.18492