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arXiv · 1008.2536

Contrast between spin and valley degrees of freedom

T. Gokmen·Medini Padmanabhan·M. Shayegan
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Abstract

We measure the renormalized effective mass (m*) of interacting two-dimensional electrons confined to an AlAs quantum well while we control their distribution between two spin and two valley subbands. We observe a marked contrast between the spin and valley degrees of freedom: When electrons occupy two spin subbands, m* strongly depends on the valley occupation, but not vice versa. Combining our m* data with the measured spin and valley susceptibilities, we find that the renormalized effective Lande g-factor strongly depends on valley occupation, but the renormalized conduction-band deformation potential is nearly independent of the spin occupation.

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T. Gokmen, Medini Padmanabhan, M. Shayegan. 2010-08-15. Contrast between spin and valley degrees of freedom. https://doi.org/10.1103/physrevb.81.235305

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