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arXiv · 1912.08006

Probing Electron-Electron Interactions with a Quantum Antidot

Lee C. Bassett
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Abstract

In the integer quantum Hall (IQH) regime, an antidot provides a finite, controllable `edge' of quantum Hall fluid that is an ideal laboratory for investigating the collective dynamics of large numbers of interacting electrons. Transport measurements of single antidots probe the excitation spectra of the antidot edge, and gate-defined antidot devices offer the flexibility to vary both the antidot's dimensions and its couplings to extended IQH edge modes which serve as leads. We also use the spin-selectivity of the IQH edge modes to perform spin-resolved transport measurements, from which we can infer the antidot spin-structure. This thesis describes a combination of such transport experiments and related computational models designed to investigate the effects of electron-electron interactions in quantum antidots, with general implications for the physics of spin and charge in IQH systems.

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Lee C. Bassett. 2019-12-17. Probing Electron-Electron Interactions with a Quantum Antidot. https://arxiv.org/abs/1912.08006

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