Chiral Transport of Hot Carriers in Graphene in the Quantum Hall Regime.

Autor: Cao B; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States., Grass T; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States.; ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona) 08860, Spain.; DIPC─Donostia International Physics Center, San Sebastian20018, Spain.; Ikerbasque─Basque Foundation for Science, Bilbao48013, Spain., Gazzano O; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States., Patel KA; L-NESS, Department of Physics, Politecnico di Milano, Via Anzani 42, 22100Como, Italy., Hu J; National Institute of Standards and Technology, Gaithersburg, Maryland20878, United States., Müller M; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States., Huber-Loyola T; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States., Anzi L; L-NESS, Department of Physics, Politecnico di Milano, Via Anzani 42, 22100Como, Italy., Watanabe K; National Institute for Materials Science, 1-1 Namiki, 305-0044Tsukuba, Japan., Taniguchi T; National Institute for Materials Science, 1-1 Namiki, 305-0044Tsukuba, Japan., Newell DB; National Institute of Standards and Technology, Gaithersburg, Maryland20878, United States., Gullans M; Joint Center for Quantum Information and Computer Science, NIST/University of Maryland, College Park, Maryland20742, United States., Sordan R; L-NESS, Department of Physics, Politecnico di Milano, Via Anzani 42, 22100Como, Italy., Hafezi M; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States.; IREAP, University of Maryland, College Park, Maryland20742, United States., Solomon GS; Joint Quantum Institute, NIST/University of Maryland, College Park, Maryland20742, United States.; Department of Physics and IPAS, University of Adelaide, Adelaide, South Australia5005, Australia.
Jazyk: angličtina
Zdroj: ACS nano [ACS Nano] 2022 Nov 22; Vol. 16 (11), pp. 18200-18209. Date of Electronic Publication: 2022 Nov 03.
DOI: 10.1021/acsnano.2c05502
Abstrakt: Photocurrent (PC) measurements can reveal the relaxation dynamics of photoexcited hot carriers beyond the linear response of conventional transport experiments, a regime important for carrier multiplication. Here, we study the relaxation of carriers in graphene in the quantum Hall regime by accurately measuring the PC signal and modeling the data using optical Bloch equations. Our results lead to a unified understanding of the relaxation processes in graphene over different magnetic field strength regimes, which is governed by the interplay of Coulomb interactions and interactions with acoustic and optical phonons. Our data provide clear indications of a sizable carrier multiplication. Moreover, the oscillation pattern and the saturation behavior of PC are manifestations of not only the chiral transport properties of carriers in the quantum Hall regime but also the chirality change at the Dirac point, a characteristic feature of a relativistic quantum Hall effect.
Databáze: MEDLINE