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arXiv · 0807.1327

Effective mass suppression in dilute, spin-polarized two-dimensional electron systems

Medini Padmanabhan·T. Gokmen·N. C. Bishop·M. Shayegan
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Abstract

We report effective mass (m*) measurements, via analyzing the temperature dependence of the Shubnikov-de Haas oscillations, for dilute, interacting, two-dimensional electron systems (2DESs) occupying a single conduction-band valley in AlAs quantum wells. When the 2DES is partially spin-polarized, m* is larger than its band value, consistent with previous results on various 2DESs. However, as we fully spin polarize the 2DES by subjecting it to strong parallel magnetic fields, m* is unexpectedly suppressed and falls even below the band mass.

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Medini Padmanabhan, T. Gokmen, N. C. Bishop, M. Shayegan. 2008-07-08. Effective mass suppression in dilute, spin-polarized two-dimensional electron systems. https://doi.org/10.1103/physrevlett.101.026402

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