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Valley susceptibility of an interacting two-dimensional electron system

O. Gunawan·Y. P. Shkolnikov·K. Vakili·T. Gokmen·E. P. De Poortere·M. Shayegan
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Abstract

We report direct measurements of the valley susceptibility, the change of valley population in response to applied symmetry-breaking strain, in an AlAs two-dimensional electron system. As the two-dimensional density is reduced, the valley susceptibility dramatically increases relative to its band value, reflecting the system's strong electron-electron interaction. The increase has a remarkable resemblance to the enhancement of the spin susceptibility and establishes the analogy between the spin and valley degrees of freedom.

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O. Gunawan, Y. P. Shkolnikov, K. Vakili, T. Gokmen, E. P. De Poortere, M. Shayegan. 2006-05-29. Valley susceptibility of an interacting two-dimensional electron system. https://doi.org/10.1103/physrevlett.97.186404

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