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Possible evidence of a spontaneous spin-polarization in mesoscopic 2D electron systems

A. Ghosh·C. J. B. Ford·M. Pepper·H. E. Beere·D. A. Ritchie
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Abstract

We have experimentally studied the non-equilibrium transport in low-density clean 2D electron systems at mesoscopic length scales. At zero magnetic field (B), a double-peak structure in the non-linear conductance was observed close to the Fermi energy in the localized regime. From the behavior of these peaks at non-zero B, we could associate them to the opposite spin states of the system, indicating a spontaneous spin polarization at B = 0. Detailed temperature and disorder dependence of the structure shows that such a splitting is a ground state property of the low-density 2D systems.

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A. Ghosh, C. J. B. Ford, M. Pepper, H. E. Beere, D. A. Ritchie. 2003-10-27. Possible evidence of a spontaneous spin-polarization in mesoscopic 2D electron systems. https://doi.org/10.1103/physrevlett.92.116601

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