18 research outputs found
Quantum correlations between two distant cavity QED systems coupled by a mechanical resonator
Achieving quantum correlations between two distant systems is a desirable
feature for quantum networking. In this work, we study a system composed of two
quantum emitter-cavity subsystems spatially separated. A mechanical resonator
couples to either both quantum emitters or both cavities leading to quantum
correlations between both subsystems such as non-local light-matter dressed
states and cavity-cavity normal mode splitting. These indirect couplings can be
explained by an effective Hamiltonian for large energy detuning between the
mechanical resonator and the atoms/cavities. Moreover, it is found optimal
conditions for the physical parameters of the system in order to maximize the
entanglement of such phonon-mediated couplings
Polariton Lasing in a Multilevel Quantum Dot Strongly Coupled To a Single Photon Mode
We present an approximate analytic expression for the photoluminescence
spectral function of a model polariton system, which describes a quantum dot,
with a finite number of fermionic levels, strongly interacting with the lowest
photon mode of a pillar microcavity. Energy eigenvalues and wavefunctions of
the electron-hole-photon system are obtained by numerically diagonalizing the
Hamiltonian. Pumping and photon losses through the cavity mirrors are described
with a master equation, which is solved in order to determine the stationary
density matrix. The photon first-order correlation function, from which the
spectral function is found, is computed with the help of the Quantum Regression
Theorem. The spectral function qualitatively describes the polariton lasing
regime in the model, corresponding to pumping rates two orders of magnitude
lower than those needed for ordinary (photon) lasing. The second-order
coherence functions for the photon and the electron-hole subsystems are
computed as functions of the pumping rate.Comment: version accepted in Phys. Rev.
Density operator of a system pumped with polaritons: A Jaynes-Cummings like approach
We investigate the effects of considering two different incoherent pumpings
over a microcavity-quantum dot system modelled using the Jaynes-Cummings
Hamiltonian. When the system is incoherently pumped with polaritons it is able
to sustain a large number of photons inside the cavity with Poisson-like
statistics in the stationary limit, and also leads to a separable
exciton-photon state. We also investigate the effects of both types of pumpings
(Excitonic and Polaritonic) in the emission spectrum of the cavity. We show
that the polaritonic pumping as considered here is unable to modify the
dynamical regimes of the system as the excitonics pumping does. Finally, we
obtain a closed form expression for the negativity of the density matrices that
the quantum master equation considered here generates.Comment: 16 pages, 4 figure