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Hole maximum density droplets of an antidot in strong magnetic fields

N. Y. Hwang·S. -R. Eric Yang·H. -S. Sim·Hangmo Yi
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Abstract

We investigate a quantum antidot in the integer quantum Hall regime (the filling factor is two) by using a Hartree-Fock approach and by transforming the electron antidot into a system which confines holes via an electron-hole transformation. We find that its ground state is the maximum density droplet of holes in certain parameter ranges. The competition between electron-electron interactions and the confinement potential governs the properties of the hole droplet such as its spin configuration. The ground-state transitions between the droplets with different spin configurations occur as magnetic field varies. For a bell-shape antidot containing about 300 holes, the features of the transitions are in good agreement with the predictions of a recently proposed capacitive interaction model for antidots as well as recent experimental observations. We show this agreement by obtaining the parameters of the capacitive interaction model from the Hartree-Fock results. An inverse parabolic antidot is also studied. Its ground-state transitions, however, display different magnetic-field dependence from that of a bell-shape antidot. Our study demonstrates that the shape of antidot potential affects its physical properties significantly.

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N. Y. Hwang, S. -R. Eric Yang, H. -S. Sim, Hangmo Yi. 2004-04-22. Hole maximum density droplets of an antidot in strong magnetic fields. https://doi.org/10.1103/physrevb.70.085322

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