Many-body features caused by Coulomb correlations are of great importance for understanding phenomena pertaining to polariton systems in semiconductor microcavities, i.e. electron–hole–photon systems. Remarkable many-body effects are shown to exist in both thermal-equilibrium phases and non-equilibrium lasing states. We then show a unified framework for connecting the thermal-equilibrium and the non-equilibrium steady states based on a non-equilibrium Green's function approach. Bose–Einstein condensate (BEC)–Bardeen–Cooper–Schrieffer (BCS)-laser crossovers are investigated by using this approach.Many-body features caused by Coulomb correlations are of great importance for understanding phenomena pertaining to polariton systems in semiconductor microcavities, i.e. electron–hole–photon systems. Remarkable many-body effects are shown to exist in both thermal-equilibrium phases and non-equilibrium lasing states. We then show a unified framework for connecting the thermal-equilibrium and the non-equilibrium steady states based on a non-equilibrium Green's function approach. Bose–Einstein condensate (BEC)–Bardeen–Cooper–Schrieffer (BCS)-laser crossovers are investigated by using this approach.

New Journal of PhysicsJun 1, 201248 citations

BEC to BCS Crossover from Superconductors to Polaritons

Alexander Edelman, P. B. Littlewood

Cambridge University Press eBooksOct 4, 20182 citations

BCS-BEC crossover in a system of microcavity polaritons

Jonathan Keeling, P. R. Eastham, Marzena Hanna Szymańska +1 more

We investigate the thermodynamics and signatures of a polariton condensate over a range of densities, using a model of microcavity polaritons with internal structure. We determine a phase diagram for this system including fluctuation corrections to the mean-field theory. At low densities the condensation temperature ${T}_{c}$ behaves like that for point bosons. At higher densities, when ${T}_{c}$ approaches the Rabi splitting, ${T}_{c}$ deviates from the form for point bosons, and instead approaches the result of a BCS-like mean-field theory. This crossover occurs at densities much less than the Mott density. We show that current experiments are in a density range where the phase boundary is described by the BCS-like mean-field boundary. We investigate the influence of inhomogeneous broadening and detuning of excitons on the phase diagram.We investigate the thermodynamics and signatures of a polariton condensate over a range of densities, using a model of microcavity polaritons with internal structure. We determine a phase diagram for this system including fluctuation corrections to the mean-field theory. At low densities the condensation temperature ${T}_{c}$ behaves like that for point bosons. At higher densities, when ${T}_{c}$ approaches the Rabi splitting, ${T}_{c}$ deviates from the form for point bosons, and instead approaches the result of a BCS-like mean-field theory. This crossover occurs at densities much less than the Mott density. We show that current experiments are in a density range where the phase boundary is described by the BCS-like mean-field boundary. We investigate the influence of inhomogeneous broadening and detuning of excitons on the phase diagram.

arXiv:cond-mat/0503184Physical Review BSep 19, 2005121 citations

Novel soliton in dipolar BEC caused by the quantum fluctuations

Pavel A. Andreev

arXiv:2009.12720The European Physical Journal DFeb 1, 20214 citations

{T}_{c}

behaves like that for point bosons. At higher densities, when

{T}_{c}

approaches the Rabi splitting,

{T}_{c}

deviates from the form for point bosons, and instead approaches the result of a BCS-like mean-field theory. This crossover occurs at densities much less than the Mott density. We show that current experiments are in a density range where the phase boundary is described by the BCS-like mean-field boundary. We investigate the influence of inhomogeneous broadening and detuning of excitons on the phase diagram.