Anomalous High-Temperature Magnetoresistance in a Dilute 2D Hole System.
Phys Rev Lett
; 130(26): 266302, 2023 Jun 30.
Article
em En
| MEDLINE
| ID: mdl-37450788
ABSTRACT
We report an unusual magnetoresistance that strengthens with the temperature in a dilute two-dimensional (2D) hole system in GaAs/AlGaAs quantum wells with densities p=1.98-0.99×10^{10}/cm^{2} where r_{s}, the ratio between Coulomb energy and Fermi energy, is as large as 20-30. We show that, while the system exhibits a negative parabolic magnetoresistance at low temperatures (â²0.4 K) characteristic of an interacting Fermi liquid, a positive magnetoresistance emerges unexpectedly at higher temperatures, and grows with increasing temperature even in the regime Tâ¼E_{F}, close to the Fermi energy. This unusual positive magnetoresistance at high temperatures can be attributed to the viscous transport of 2D hole fluid in the hydrodynamic regime where holes scatter frequently with each other. These findings give insight into the collective transport of strongly interacting carriers in the r_{s}â«1 regime and new routes toward magnetoresistance at high temperatures.
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Base de dados:
MEDLINE
Assunto principal:
Temperatura Baixa
/
Hidrodinâmica
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article