Observation of bright polariton solitons in a semiconductor microcavity

TL;DR

This paper reports the first experimental observation of bright polariton solitons in a semiconductor microcavity, highlighting their potential for ultrafast optical information processing due to their non-diffracting, localized wavepackets.

Contribution

It provides the first experimental evidence of bright polariton solitons in a strongly coupled semiconductor microcavity, demonstrating their unique properties and potential for ultrafast applications.

Findings

Bright polariton solitons are non-diffracting, localized wavepackets.

They are excited on picosecond timescales, enabling ultrafast switching.

These solitons rely on a balance between losses and external pumping.

Abstract

Microcavity polaritons are composite half-light half-matter quasi-particles, which have recently been demonstrated to exhibit rich physical properties, such as non-equilibrium Bose-Einstein condensation, parametric scattering and superfluidity. At the same time, polaritons have some important advantages over photons for information processing applications, since their excitonic component leads to weaker diffraction and stronger inter-particle interactions, implying, respectively, tighter localization and lower powers for nonlinear functionality. Here we present the first experimental observations of bright polariton solitons in a strongly coupled semiconductor microcavity. The polariton solitons are shown to be non-diffracting high density wavepackets, that are strongly localised in real space with a corresponding broad spectrum in momentum space. Unlike solitons known in other matter-wave systems such as Bose condensed ultracold atomic gases, they are non-equilibrium and rely on a balance between losses and external pumping. Microcavity polariton solitons are excited on picosecond timescales, and thus have significant benefits for ultrafast switching and transfer of information over their light only counterparts, semiconductor cavity lasers (VCSELs), which have only nanosecond response time.