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Observation of Quantum Hall Valley Skyrmions

Y. P. Shkolnikov·S. Misra·N. C. Bishop·E. P. De Poortere·M. Shayegan
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Abstract

We report measurements of the interaction-induced quantum Hall effect in a spin-polarized AlAs two-dimensional electron system where the electrons occupy two in-plane conduction band valleys. Via the application of in-plane strain, we tune the energies of these valleys and measure the energy gap of the quantum Hall state at filling factor $ν$ = 1. The gap has a finite value even at zero strain and, with strain, rises much faster than expected from a single-particle picture, suggesting that the lowest energy charged excitations at $ν=1$ are "valley Skyrmions".

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Y. P. Shkolnikov, S. Misra, N. C. Bishop, E. P. De Poortere, M. Shayegan. 2005-05-05. Observation of Quantum Hall Valley Skyrmions. https://doi.org/10.1103/physrevlett.95.066809

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