Temporal dark polariton solitons

Abstract

Received XX Month XXXX; revised XX Month, XXXX; accepted XX Month XXXX; posted XX Month XXXX (Doc. ID XXXXX); published XX Month XXXX We predict that strong coupling between waveguide photons and excitons of quantum well embedded into waveguide results in the formation of hybrid dark and anti-dark light-matter solitons. Such temporal solitons exist due to interplay between repulsive excitonic nonlinearity and giant group velocity dispersion arising in the vicinity of excitonic resonance. Such fully conservative states do not require external pumping to counteract losses and form continuous families parameterized by the power-dependent phase shift and velocity of their motion. Dark solitons are stable in the considerable part of their existence domain, while anti-dark solitons are always unstable. Both families exist outside forbidden frequency gap of the linear system.Using strong light-matter coupling and record high levels of nonlinearity in the exciton-polariton micro-resonators, waveguides, and periodic lattices is becoming a rapidly developing branch of photonics showing a plethora of fundamental physical effects at the interface between optics and condensed matter physics [1]. Recently planar waveguides and photonic wires operating in the regime of strong coupling between photons and quantum-well excitons have been demonstrated [2][3][4][5] and used for observation of temporal and spatio-temporal solitons. The effective nonlinear parameter  [6] in these waveguides can reach . Thus, such waveguides represent an excellent experimental platform for the demonstration of ultra-low-power self-sustained excitations.Optical modes of a waveguide with single or multiple quantum wells can couple to an excitonic resonance [2][3][4]. In the presence of waveguide spatial localization is mediated by the total internal reflection, i.e. no Bragg mirrors in the cladding are necessary. Under these conditions the photon component of the polariton quasi-particle is given by the electro-magnetic waveguide mode detuned far away from the waveguide cut-off and having the dispersion profile linear over the bandwidth of several excitonic resonances. The latter are well described by the Lorentz oscillator model with the resonance energy upshifted through the repulsive excitonexciton interaction, which produces net defocusing nonlinearity for polaritons. This system features upper and lower polariton branches having respectively anomalous and normal group velocity dispersions. The latter case in combination with the defocusing excitonic nonlinearity gives rise to bright temporal solitons that have been demonstrated experimentally in [2], while the former case suggests the existence of dark temporal solitons that are under investigation in this Letter.One should mention the link between temporal excitations studied in this Letter and spatial dark polariton solitons forming in planar microresonators upon interaction with an obstacle [8,9]. As these solitons propagate with some slow velocities of few percent of the light velocity, they ...

Dynamics of defect-induced dark solitons in an exciton-polariton condensate

“…Many previously reported experimental results are accurately modeled by the Gross-Pitaevskii equation (GPE). The use of GPE makes it possible to describe fundamental properties of dark and bright solitons in a polariton condensate, such as their dynamics, stability, and continous emission [27][28][29][30][31][32][33][34]. Successful creation of nonlinear excitations and their manipulation gave rise to a new concept of information processing based on vortices and soliton dynamics [35][36][37].…”