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arXiv · 1510.06900

Goldstone mode stochastization in quantum Hall ferromagnet

A. V. Larionov·L. V. Kulik·S. Dickmann·I. V. Kukushkin
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Abstract

Experimental and theoretical studies of the coherent spin dynamics of two-dimensional GaAs/AlGaAs electron gas were performed. The system in the quantum Hall ferromagnet state exhibits a spin relaxation mechanism that is determined by many-particle Coulomb interactions. In addition to the spin exciton with changes in the spin quantum numbers of $\delta S\!=\!\delta S_z \!=\!-1$, the quantum Hall ferromagnet supports a Goldstone spin exciton that changes the spin quantum numbers to $\delta S\!=\!0$ and $\delta S_z\!=\!-1$, which corresponds to a coherent spin rotation of the entire electron system to a certain angle. The Goldstone spin exciton decays through a specific relaxation mechanism that is unlike any other collective spin state.

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A. V. Larionov, L. V. Kulik, S. Dickmann, I. V. Kukushkin. 2015-10-23. Goldstone mode stochastization in quantum Hall ferromagnet. https://doi.org/10.1103/physrevb.92.165417

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