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arXiv · 1510.05299

Quasiparticle Mass Enhancement and Fermi Surface Shape Modification in Oxide Two-Dimensional Electron Gases

John R. Tolsma·Alessandro Principi·Reza Asgari·Marco Polini·Allan H. MacDonald
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Abstract

We propose a model intended to qualitatively capture the electron-electron interaction physics of two-dimensional electron gases formed near transition-metal oxide heterojunctions containing $t_{2g}$ electrons with a density much smaller than one electron per metal atom. Two-dimensional electron systems of this type can be described perturbatively using a $GW$ approximation which predicts that Coulomb interactions enhance quasiparticle effective masses more strongly than in simple two-dimensional electron gases, and that they reshape the Fermi surface, reducing its anisotropy.

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John R. Tolsma, Alessandro Principi, Reza Asgari, Marco Polini, Allan H. MacDonald. 2015-10-18. Quasiparticle Mass Enhancement and Fermi Surface Shape Modification in Oxide Two-Dimensional Electron Gases. https://doi.org/10.1103/physrevb.93.045120

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