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Spin-independent effective mass in a valley-degenerate electron system

Suhas Gangadharaiah·Dmitrii L. Maslov
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Abstract

In a generic spin-polarized Fermi liquid, the masses of spin-up and spin-down electrons are expected to be different and to depend on the degree of polarization. This expectation is not confirmed by the experiments on two-dimensional heterostructures. We consider a model of an $N$-fold degenerate electron gas. It is shown that in the large-N limit, the mass is enhanced via a polaronic mechanism of emission/absorption of virtual plasmons. As plasmons are classical collective excitations, the resulting mass does not depend on $N$, and thus on polarization, to the leading order in 1/N. We evaluate the 1/N corrections and show that they are small even for N=2.

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Suhas Gangadharaiah, Dmitrii L. Maslov. 2005-05-31. Spin-independent effective mass in a valley-degenerate electron system. https://doi.org/10.1103/physrevlett.95.186801

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