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Various spin-polarization states beyond the maximum-density droplet: a quantum Monte Carlo study

S. Siljamaki·A. Harju·R. M. Nieminen·V. A. Sverdlov·P. Hyvonen
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Abstract

Using variational quantum Monte Carlo method, the effect of Landau-level mixing on the lowest-energy--state diagram of small quantum dots is studied in the magnetic field range where the density of magnetic flux quanta just exceeds the density of electrons. An accurate analytical many-body wave function is constructed for various angular momentum and spin states in the lowest Landau level, and Landau-level mixing is then introduced using a Jastrow factor. The effect of higher Landau levels is shown to be significant; the transition lines are shifted considerably towards higher values of magnetic field and certain lowest-energy states vanish altogether.

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S. Siljamaki, A. Harju, R. M. Nieminen, V. A. Sverdlov, P. Hyvonen. 2001-12-13. Various spin-polarization states beyond the maximum-density droplet: a quantum Monte Carlo study. https://doi.org/10.1103/physrevb.65.121306

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