Mode locking and mode competition in a nonequilibrium solid-state condensate

Abstract

A trapped polariton condensate with continuous pumping and decay is analyzed using a generalized GrossPitaevskii model. Whereas an equilibrium condensate is characterized by a macroscopic occupation of a ground state, here the steady states take more general forms. Some are characterized by a large population in an excited state; others by large populations in several states, which may overlap spatially. In the latter case, the highly populated states synchronize to a common frequency above a critical density. At intermediate densities, they can drive condensation in other trap modes by parametric scattering. Estimates for the critical density of the synchronization transition are consistent with experiments.

Finite-momentum condensation in a pumped microcavity

“…19 Here the nonlinearity corresponds to the depletion of the exciton population by the growth of the condensate. This will reduce the gain 13 for collective modes of similar energies, suggesting that a single plane wave ͑Fulde-Ferrel͒ state may be favored. Although these nonlinearities determine a particular form for the condensate it is unlikely they will lead to a homogeneous state so we do not treat them in detail here.…”

Symmetry-Breaking Effects for Polariton Condensates in Double-Well Potentials

“…A similar approach, in the absence of external confining potential, has been used in Ref. [70] for a polariton laser. We start by considering the corresponding linear eigenproblem which reads:…”

Localization and self-trapping in driven-dissipative polariton condensates

“…This creates an interesting phenomenology, blending that of equilibrium condensates, which are dominated by interactions, with that of systems such as lasers, which are dominated by dissipation. For example, in two-mode systems the steady state can have density oscillations, which correspond to the a.c. Josephson effect [12,[18][19][20][21][22][23]. Such oscillations also occur in the dissipationdominated regime, where they reflect the coexistence of two condensates of different frequencies, as in a multimode laser [19].…”

“…For example, in two-mode systems the steady state can have density oscillations, which correspond to the a.c. Josephson effect [12,[18][19][20][21][22][23]. Such oscillations also occur in the dissipationdominated regime, where they reflect the coexistence of two condensates of different frequencies, as in a multimode laser [19]. Indeed at the qualitative level many important phenomena, like gap solitons [14,15], vortices [16], and condensate localization [17,24,25], occur in both interaction-dominated and dissipation-dominated condensates.…”

“…In this paper we reexamine how the combination of gain, loss, and interactions affects the behavior of a polariton condensate in the simple two-state model of a Josephson junction [18,19,21]. The two states could correspond to neighboring local minima of a double-well potential in a coupled photonic molecule [13], or in a planar structure at a suitable point in a disorder potential [12].…”