TY - JOUR

T1 - Phonon drag thermoelectric phenomena in mesoscopic two-dimensional conductors

T2 - Current stripes, large Nernst effect, and influence of electron-electron interaction

AU - Raichev, O. E.

AU - Gusev, G. M.

AU - Hernandez, F. G.G.

AU - Levin, A. D.

AU - Bakarov, A. K.

N1 - Funding Information: The authors acknowledge financial support of this work by FAPESP and CNPq (Brazilian agencies). Publisher Copyright: © 2020 American Physical Society. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/11/6

Y1 - 2020/11/6

N2 - The interaction of electrons with a flux of ballistic phonons leads to excitation of many angular harmonics of an electron distribution function. We show that this property dramatically modifies the magnetothermoelectric phenomena in two-dimensional electron systems with boundaries. By considering classical magnetotransport of electrons in a narrow channel with partly diffusive boundary scattering, we show that the phonon flux excites a pattern of current stripes with alternating directions of propagation along the channel. The Nernst voltage due to phonon drag appears already in the classical transport regime and can be comparable with the Seebeck voltage, while the latter acquires a dependence on the magnetic field. The temperature dependence of these voltages shows an unusual behavior determined by relaxation of higher-order harmonics of the distribution function via electron-electron scattering. Our experimental studies of mesoscopic samples based on high-quality GaAs quantum wells confirm the main properties of the thermoelectric response suggested by the theory.

AB - The interaction of electrons with a flux of ballistic phonons leads to excitation of many angular harmonics of an electron distribution function. We show that this property dramatically modifies the magnetothermoelectric phenomena in two-dimensional electron systems with boundaries. By considering classical magnetotransport of electrons in a narrow channel with partly diffusive boundary scattering, we show that the phonon flux excites a pattern of current stripes with alternating directions of propagation along the channel. The Nernst voltage due to phonon drag appears already in the classical transport regime and can be comparable with the Seebeck voltage, while the latter acquires a dependence on the magnetic field. The temperature dependence of these voltages shows an unusual behavior determined by relaxation of higher-order harmonics of the distribution function via electron-electron scattering. Our experimental studies of mesoscopic samples based on high-quality GaAs quantum wells confirm the main properties of the thermoelectric response suggested by the theory.

KW - THERMOPOWER

KW - HETEROSTRUCTURES

KW - GAS

UR - http://www.scopus.com/inward/record.url?scp=85096305661&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.102.195301

DO - 10.1103/PhysRevB.102.195301

M3 - Article

AN - SCOPUS:85096305661

VL - 102

JO - Physical Review B

JF - Physical Review B

SN - 2469-9950

IS - 19

M1 - 195301

ER -