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arXiv · 0810.1956

Dependence of Effective Mass on Spin and Valley Degrees of Freedom

T. Gokmen·Medini Padmanabhan·M. Shayegan
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Abstract

We measure the effective mass (m*) of interacting two-dimensional electrons confined to an AlAs quantum well while we change the conduction-band valley occupation and the spin polarization via the application of strain and magnetic field, respectively. Compared to its band value, m* is enhanced unless the electrons are fully valley and spin polarized. Incidentally, in the fully spin- and valley-polarized regime, the electron system exhibits an insulating behavior.

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T. Gokmen, Medini Padmanabhan, M. Shayegan. 2008-10-11. Dependence of Effective Mass on Spin and Valley Degrees of Freedom. https://doi.org/10.1103/physrevlett.101.146405

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