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Large Skyrmions in an Al(0.13)Ga(0.87)As Quantum Well

S. P. Shukla·M. Shayegan·S. R. Parihar·S. A. Lyon·N. R. Cooper·A. A. Kiselev
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Abstract

We report tilted-field magnetotransport measurements of two-dimensional electron systems in a 200 Angstrom-wide Al(0.13)Ga(0.87)As quantum well. We extract the energy gap for the quantum Hall state at Landau level filling ν=1 as a function of the tilt angle. The relatively small effective Lande g-factor (g ~ 0.043) of the structure leads to skyrmionic excitations composed of the largest number of spins yet reported (s ~ 50). Although consistent with the skyrmion size observed, Hartree-Fock calculations, even after corrections, significantly overestimate the energy gaps over the entire range of our data.

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S. P. Shukla, M. Shayegan, S. R. Parihar, S. A. Lyon, N. R. Cooper, A. A. Kiselev. 1999-10-25. Large Skyrmions in an Al(0.13)Ga(0.87)As Quantum Well. https://doi.org/10.1103/physrevb.61.4469

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