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

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 $N\le 30$ 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.

References in corpus (9)

• Strongly correlated 2D quantum phases with cold polar molecules: controlling the shape of the interaction potential
• Quantum phase transition in a two-dimensional system of dipoles
• Cold polar molecules in 2D traps: Tailoring interactions with external fields for novel quantum phases
• Classical and quantum Coulomb crystals
• Wigner supersolid of excitons in electron-hole bilayers
• Ground state of a confined Yukawa plasma
• Quantum melting of a crystal of dipolar bosons
• Ground state of a confined Yukawa plasma including correlation effects
• Collective excitations in electron-hole bilayers