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Phonon emission and absorption in the fractional quantum Hall effect

F. Schulze-Wischeler·U. Zeitler·M. Monka·F. Hohls·R. J. Haug·K. Eberl
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Abstract

We investigate the time dependent thermal relaxation of a two-dimensional electron system in the fractional quantum Hall regime where ballistic phonons are used to heat up the system to a non-equilibrium temperature. The thermal relaxation of a 2DES at $ν=1/2$ can be described in terms of a broad band emission of phonons, with a temperature dependence proportional to $T^4$. In contrast, the relaxation at fractional filling $ν=2/3$ is characterized by phonon emission around a single energy, the magneto-roton gap. This leads to a strongly reduced energy relaxation rate compared to $ν=1/2$ with only a weak temperature dependence for temperatures 150 mK $< T <$ 400 mK.

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F. Schulze-Wischeler, U. Zeitler, M. Monka, F. Hohls, R. J. Haug, K. Eberl. 2000-09-22. Phonon emission and absorption in the fractional quantum Hall effect. https://doi.org/10.1016/s0921-4526(01)00293-9

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