Solitons in cavity-QED arrays containing interacting qubits

Abstract

We reveal the existence of polariton soliton solutions in the array of weakly coupled optical cavities, each containing an ensemble of interacting qubits. An effective complex Ginzburg-Landau equation is derived in the continuum limit taking into account the effects of cavity field dissipation and qubit dephasing. We have shown that an enhancement of the induced nonlinearity can be achieved by two order of the magnitude with a negative interaction strength which implies a large negative qubit-field detuning as well. Bright solitons are found to be supported under perturbations only in the upper (optical) branch of polaritons, for which the corresponding group velocity is controlled by tuning the interacting strength. With the help of perturbation theory for solitons, we also demonstrate that the group velocity of these polariton solitons is suppressed by the diffusion process.

Tunneling-assisted optical information storage with lattice polariton solitons in cavity-QED arrays

“…For the systems based on alkali-metal atoms, the limiting time of quantum storage process typically approaches tens of nanoseconds (cf. [15]). However, for especially prepared ensembles of rare-earth optical centers, the transition lifetime can achieve the value of a few milliseconds [36].…”

“…For this approach, by substituting Eq. (16) into (15) and keeping LB polariton terms only, we arrive at…”

“…Strictly speaking, it is possible to treat the operatorŝ a 1,n andâ 2,n describing particles at lower and upper levels, [15]. When number N at each cavity is macroscopical but not so large, one can keep all the terms in the expansion ofâ 1,n .…”

“…III, we introduce a coupled atom-light excitation basis that is the polariton basis for the lattice system. Apart from results obtained by us previously [15], LB polaritons occurring at each site of the cavity array are a subject of our study in the rest of the paper. In Sec.…”

“…Moreover, a strong Kerr-type nonlinearity caused by two-body polariton-polariton interaction leads to the formation of bright polariton solitons [13][14][15].…”