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arXiv · 1408.0631

Strongly Interacting Holes in Ge/Si Nanowires

Franziska Maier·Tobias Meng·Daniel Loss
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Abstract

We consider holes confined to Ge/Si core/shell nanowires subject to strong Rashba spin-orbit interaction and screened Coulomb interaction. Such wires can, for instance, serve as host systems for Majorana bound states. Starting from a microscopic model, we find that the Coulomb interaction strongly influences the properties of experimentally realistic wires. To show this, a Luttinger liquid description is derived based on a renormalization group analysis. This description in turn allows to calculate the scaling exponents of various correlation functions as a function of the microscopic system parameters. It furthermore permits to investigate the effect of Coulomb interaction on a small magnetic field, which opens a strongly anisotropic partial gap.

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Franziska Maier, Tobias Meng, Daniel Loss. 2014-08-04. Strongly Interacting Holes in Ge/Si Nanowires. https://doi.org/10.1103/physrevb.90.155437

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