Entanglement and phase transitions in a exciton-polariton bec confined in a photonic crystal nanocavity (2013)
In this work we study a polariton-exciton system confined in photonic crystal nanocavity with embedded quantum dot. Using a separable state of the type BCS, for the matter subsystem, product by a coherent state, for the photonic mode, we compute the ground state energy of N polaritons. Also, we characterize the quantum coherence in the system using entanglement and discord, calculated both from the pair density matrix. Finally, we introduce temperature and magnetic field to our model and we obtain signatures of phase transitions in the quantum correlations of the system.