• 文献标题:   Multicomponent Electron-Hole Superfluidity and the BCS-BEC Crossover in Double Bilayer Graphene
  • 文献类型:   Article
  • 作  者:   CONTI S, PERALI A, PEETERS FM, NEILSON D
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW LETTERS
  • ISSN:   0031-9007 EI 1079-7114
  • 通讯作者地址:   Univ Camerino
  • 被引频次:   6
  • DOI:   10.1103/PhysRevLett.119.257002
  • 出版年:   2017

▎ 摘  要

Superfluidity in coupled electron-hole sheets of bilayer graphene is predicted here to be multicomponent because of the conduction and valence bands. We investigate the superfluid crossover properties as functions of the tunable carrier densities and the tunable energy band gap Eg. For small band gaps there is a significant boost in the two superfluid gaps, but the interaction-driven excitations from the valence to the conduction band can weaken the superfluidity, even blocking the system from entering the Bose-Einstein condensate (BEC) regime at low densities. At a given larger density, a band gap E-g similar to 80-120 meV can carry the system into the strong-pairing multiband BCS-BEC crossover regime, the optimal range for realization of high-Tc superfluidity.