Magnetic-field-induced cavity protection for intersubband polaritons

TL;DR

This paper investigates how a strong perpendicular magnetic field can modify the optical transition lineshape in a disordered quantum well, leading to a novel cavity protection effect that narrows polariton linewidths for potential technological applications.

Contribution

It introduces a new magnetic-field-induced cavity protection mechanism that reduces polariton linewidths by changing the lineshape from Lorentzian to Gaussian in disordered quantum wells.

Findings

Magnetic field transforms lineshape from Lorentzian to Gaussian.

Cavity protection significantly narrows polariton linewidths.

Implications for nonlinear polariton dynamics and polariton lasers.

Abstract

We analyse the effect of a strong perpendicular magnetic field on an intersubband transition in a disordered doped quantum well strongly coupled to an optical cavity. The magnetic field changes the lineshape of the intersubband optical transition due to the interface roughness of the quantum well from a Lorentzian to a Gaussian one. In this regime, a novel form of magnetic-field-induced cavity protection sets in, which strongly reduces the polariton linewidth to the cavity contribution only. Implications of our results for fundamental studies of nonlinear polariton dynamics and for technological applications to polariton lasers are finally highlighted.