Giant spin Meissner effect in a non-equilibrium exciton-polariton gas

TL;DR

This paper reports the first clear observation of the giant spin Meissner effect in a non-equilibrium exciton-polariton gas within semimagnetic microcavities, demonstrating partial suppression of Zeeman splitting in both condensed and uncondensed phases.

Contribution

It provides the first experimental evidence of the giant spin Meissner effect in a non-equilibrium polariton system and introduces a kinetic model to explain the observations.

Findings

Partial suppression of Zeeman energy splitting occurs in the uncondensed phase.

Giant Zeeman splitting of up to 2 meV observed in semimagnetic microcavities.

The kinetic model accurately describes both condensed and uncondensed polariton behaviors.

Abstract

The suppression of Zeeman energy splitting due to spin-dependent interactions within a Bose-Einstein condensate (the spin Meissner effect) was predicted to occur up to a certain value of magnetic field strength. We report a clear observation of this effect in semimagnetic microcavities which exhibit the giant Zeeman energy splitting between two spin-polarised polariton states as high as 2 meV, and demonstrate that partial suppression of energy difference occurs already in the uncondensed phase in a striking similarity to the up-critical superconductors in the fluctuation dominated regime. These observations are explained quantitatively by a kinetic model accounting for both the condensed and uncondensed polaritons and taking into account the non-equilibrium character of the system.