Large cumulant eigenvalue as a signature of exciton condensation

Eigenvalue Decomposition of a Cumulant Tensor with Applications

Condensation of semiconductor microcavity exciton polaritons.

A phase transition from a classical thermal mixed state to a quantum-mechanical pure state of exciton polaritons is observed in a GaAs multiple quantum-well microcavity from the decrease of the second-order coherence function. Supporting evidence is obtained from the observation of a nonlinear threshold behavior in the pump-intensity dependence of the emission, a polariton-like dispersion relat...

Statistics of Exciton Emission in a Semiconductor Microcavity: Detuning and Exciton-Exciton Effects

We consider the interaction of quantum light with an ideal semiconductor microcavity. We investigate photon statistics in different conditions and the presence of detuning and exciton-exciton interaction. We show that in the resonant interaction and absence of the exciton-exciton interaction, the state of the whole system can be considered as   coherent state. According to our results, it turns...

Field-induced exciton condensation in LaCoO3

Motivated by recent observation of magnetic field induced transition in LaCoO3 we study the effect of external field in systems close to instabilities towards spin-state ordering and exciton condensation. We show that, while in both cases the transition can be induced by an external field, temperature dependencies of the critical field have opposite slopes. Based on this result we argue that th...

Exciton condensation in coupled quantum wells

Bound electron–hole pairs—excitons—are Bose particles with small mass. Exciton Bose–Einstein condensation is expected to occur at a few degrees Kelvin—a temperature many orders of magnitude higher than for atoms. Experimentally, an exciton temperature well below 1 K is achieved in coupled quantum well (CQW) semiconductor nanostructures. In this contribution, we review briefly experiments that s...