Rotons in a hybrid Bose-Fermi system
Quantum Gases
2010-10-04 v2
Abstract
We calculate the spectrum of elementary excitations in a two-dimensional exciton superfluid in the vicinity of a two-dimensional electron gas. We show that attraction of excitons due to their scattering with free electrons may lead to formation of a roton minimum. The energy of this minimum may go below the ground state energy which manifests breaking of the superfluidity. The Berezinsky-Kosterlitz-Thouless phase transition temperature decreases due to the exciton-exciton attraction mediated by electrons.
Cite
@article{arxiv.1007.2891,
title = {Rotons in a hybrid Bose-Fermi system},
author = {I. A. Shelykh and T. Taylor and A. V. Kavokin},
journal= {arXiv preprint arXiv:1007.2891},
year = {2010}
}
Comments
Revised version with parameters of realistic GaAs double quantum well, accepted for publication in Phys. Rev. Lett