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Metastable phase in the quantum Hall ferromagnet

Vincenzo Piazza·Vittorio Pellegrini·Fabio Beltram·Werner Wegscheider
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Abstract

Time-dependent capacitance measurements reveal an unstable phase of electrons in gallium arsenide quantum well that occurs when two Landau levels with opposite spin are brought close to degeneracy by applying a gate voltage. This phase emerges below a critical temperature and displays a peculiar non-equilibrium dynamical evolution. The relaxation dynamics is found to follow a stretched exponential behavior and correlates with hysteresis loops observed by sweeping the magnetic field. These experiments indicate that metastable randomly-distributed magnetic domains are involved in the relaxation process in a way that is equivalently tunable by a change in gate voltage or temperature.

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Vincenzo Piazza, Vittorio Pellegrini, Fabio Beltram, Werner Wegscheider. 2003-03-25. Metastable phase in the quantum Hall ferromagnet. https://doi.org/10.1016/s0038-1098(03)00317-x

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