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Specific Heat of a Fractional Quantum Hall System

F. Schulze-Wischeler·U. Zeitler·C. v. Zobeltitz·F. Hohls·D. Reuter·A. D. Wieck·H. Frahm·R. J. Haug
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Abstract

Using a time-resolved phonon absorption technique, we have measured the specific heat of a two-dimensional electron system in the fractional quantum Hall effect regime. For filling factors $ν= 5/3, 4/3, 2/3, 3/5, 4/7, 2/5$ and 1/3 the specific heat displays a strong exponential temperature dependence in agreement with excitations across a quasi-particle gap. At filling factor $ν= 1/2$ we were able to measure the specific heat of a composite fermion system for the first time. The observed linear temperature dependence on temperature down to $T = 0.14$ K agrees well with early predictions for a Fermi liquid of composite fermions.

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F. Schulze-Wischeler, U. Zeitler, C. v. Zobeltitz, F. Hohls, D. Reuter, A. D. Wieck, H. Frahm, R. J. Haug. 2006-12-05. Specific Heat of a Fractional Quantum Hall System. https://doi.org/10.1103/physrevb.76.153311

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