skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

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

Authors:
; ;
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1395385
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 96; Journal Issue: 12; Related Information: CHORUS Timestamp: 2017-09-28 10:56:08; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Hanai, Ryo, Littlewood, Peter B., and Ohashi, Yoji. Dynamical instability of a driven-dissipative electron-hole condensate in the BCS-BEC crossover region. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.96.125206.
Hanai, Ryo, Littlewood, Peter B., & Ohashi, Yoji. Dynamical instability of a driven-dissipative electron-hole condensate in the BCS-BEC crossover region. United States. doi:10.1103/PhysRevB.96.125206.
Hanai, Ryo, Littlewood, Peter B., and Ohashi, Yoji. 2017. "Dynamical instability of a driven-dissipative electron-hole condensate in the BCS-BEC crossover region". United States. doi:10.1103/PhysRevB.96.125206.
@article{osti_1395385,
title = {Dynamical instability of a driven-dissipative electron-hole condensate in the BCS-BEC crossover region},
author = {Hanai, Ryo and Littlewood, Peter B. and Ohashi, Yoji},
abstractNote = {},
doi = {10.1103/PhysRevB.96.125206},
journal = {Physical Review B},
number = 12,
volume = 96,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on September 28, 2018
Publisher's Accepted Manuscript

Save / Share:
  • We theoretically investigate a Bose-condensed exciton gas out of equilibrium. Within the framework of the combined BCS-Leggett strong-coupling theory with the non-equilibrium Keldysh formalism, we show how the Bose-Einstein condensation (BEC) of excitons is suppressed to eventually disappear, when the system is in the non-equilibrium steady state. The supply of electrons and holes from the bath is shown to induce quasi-particle excitations, leading to the partial occupation of the upper branch of Bogoliubov single-particle excitation spectrum. We also discuss how this quasi-particle induction is related to the suppression of exciton BEC, as well as the stability of the steady state.
  • We interpret the recently observed spatial domain formation in spin-1 atomic condensates as a result of dynamical instability. Within the mean field theory, a homogeneous condensate is dynamically unstable (stable) for ferromagnetic (antiferromagnetic) atomic interactions. We find that this dynamical instability naturally leads to spontaneous domain formation as observed in several recent experiments for condensates with rather small numbers of atoms. For trapped condensates, our numerical simulations compare quantitatively to the experimental results, thus largely confirming the physical insight from our analysis of the homogeneous case.
  • We analyze the hydrodynamic solutions for a dilute Bose-Einstein condensate with long-range dipolar interactions in a rotating, elliptical harmonic trap. The static solutions and their regimes of dynamical instability vary nontrivially with the strength of the dipolar interactions. We comprehensively map out this behavior, and, in particular, examine the experimental routes toward unstable dynamics, which, in analogy to conventional condensates, may lead to vortex lattice formation.
  • We investigate the stability of an attractive Bose-Einstein condensate in a one-dimensional lattice in the presence of radial confinement. We find that the system is dynamically unstable for low quasimomenta and becomes stable near the band edge, in a specular fashion with respect to the repulsive case. For low interactions the instability occurs via long-wavelength excitations that produce an oscillating density pattern in both real and momentum space instead of spoiling the condensate coherence. This behavior is illustrated by simulations for the expansion of the condensate in a moving lattice.