Crystallization in Mass-Asymmetric Electron-Hole Bilayers



We consider a mass-asymmetric electron and hole bilayer. Electron and hole Coulomb correlations and electron and hole quantum effects are treated on first principles by path integral Monte Carlo methods. For a fixed layer separation we vary the mass ratio M of holes and electrons between 1 and 100 and analyze the structural changes in the system. While, for the chosen density, the electrons are in a nearly homogeneous state, the hole arrangement changes from homogeneous to localized, with increasing M, which is verified for both, mesoscopic bilayers in a parabolic trap and for a macroscopic system. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)