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Effective mass enhancement in two-dimensional electron systems: the role of interaction and disorder effects

R. Asgari·B. Davoudi·B. Tanatar
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Abstract

Recent experiments on two-dimensional (2D) electron systems have found a sharp increase in the effective mass of electrons with decreasing electron density. In an effort to understand this behavior we employ the many-body theory to calculate the quasiparticle effective mass in 2D electron systems. Because the low density regime is explored in the experiments we use the $GWΓ$ approximation where the vertex correction $Γ$ describes the correlation effects to calculate the self-energy from which the effective mass is obtained. We find that the quasiparticle effective mass shows a sharp increase with decreasing electron density. Disorder effects due to charged impurity scattering plays a crucial role in density dependence of effective mass.

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R. Asgari, B. Davoudi, B. Tanatar. 2004-01-16. Effective mass enhancement in two-dimensional electron systems: the role of interaction and disorder effects. https://doi.org/10.1016/j.ssc.2004.01.018

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