Dynamical instability of a driven-dissipative electron-hole condensate in the BCS-BEC crossover region

Journal Article · Fri Sep 01 00:00:00 EDT 2017 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.96.125206· OSTI ID:1427528

Hanai, Ryo; Littlewood, Peter B.; Ohashi, Yoji

We present a stability analysis on a driven-dissipative electron-hole condensate in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein-condensation)-crossover region. Extending the combined BCS-Leggett theory with the generalized random phase approximation (GRPA) to the non-equilibrium case by employing the Keldysh formalism, we show that the pumping-and-decay of carriers causes a depairing effect on excitons. This phenomenon gives rise to an attractive interaction between excitons in the BEC regime, as well as a supercurrent that anomalously flows anti-parallel to ∇θ(r) (where θ(r) is the phase of the condensate) in the BCS regime, both leading to dynamical instabilities of an exciton-BEC.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1427528
• Journal Information: Physical Review B, Vol. 96, Issue 12; ISSN 2469-9950
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English