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arXiv · 0804.2406

On the Coulomb-dipole transition in mesoscopic classical and quantum electron-hole bilayers

P. Ludwig·K. Balzer·A. Filinov·H. Stolz·M. Bonitz
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Abstract

We study the Coulomb-to-dipole transition which occurs when the separation $d$ of an electron-hole bilayer system is varied with respect to the characteristic in-layer distances. An analysis of the classical ground state configurations for harmonically confined clusters with $N\leq30$ reveals that the energetically most favorable state can differ from that of two-dimensional pure dipole or Coulomb systems. Performing a normal mode analysis for the N=19 cluster it is found that the lowest mode frequencies exhibit drastic changes when $d$ is varied. Furthermore, we present quantum-mechanical ground states for N=6, 10 and 12 spin-polarized electrons and holes. We compute the single-particle energies and orbitals in self-consistent Hartree-Fock approximation over a broad range of layer separations and coupling strengths between the limits of the ideal Fermi gas and the Wigner crystal.

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P. Ludwig, K. Balzer, A. Filinov, H. Stolz, M. Bonitz. 2008-04-15. On the Coulomb-dipole transition in mesoscopic classical and quantum electron-hole bilayers. https://doi.org/10.1088/1367-2630/10/8/083031

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