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Temperature and Magnetic Field Enhanced Hall Slope of a Dilute 2D Hole System in the Ballistic Regime

Xuan P. A. Gao·G. S. Boebinger·A. P. Mills Jr.·A. P. Ramirez·L. N. Pfeiffer·K. W. West
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Abstract

We report the temperature($T$) and perpendicular magnetic field($B$) dependence of the Hall resistivity $ρ_{xy}(B)$ of dilute metallic two-dimensional(2D) holes in GaAs over a broad range of temperature(0.02-1.25K). The low $B$ Hall coefficient, $R_H$, is found to be enhanced when $T$ decreases. Strong magnetic fields further enhance the slope of $ρ_{xy}(B)$ at all temperatures studied. Coulomb interaction corrections of a Fermi liquid(FL) in the ballistic regime can not explain the enhancement of $ρ_{xy}$ which occurs in the same regime as the anomalous metallic longitudinal conductivity. In particular, although the metallic conductivity in 2D systems has been attributed to electron interactions in a FL, these same interactions should reduce, {\it not enhance} the slope of $ρ_{xy}(B)$ as $T$ decreases and/or $B$ increases.

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Xuan P. A. Gao, G. S. Boebinger, A. P. Mills Jr., A. P. Ramirez, L. N. Pfeiffer, K. W. West. 2004-11-15. Temperature and Magnetic Field Enhanced Hall Slope of a Dilute 2D Hole System in the Ballistic Regime. https://doi.org/10.1103/physrevlett.93.256402

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