Immunity of intersubband polaritons to inhomogeneous broadening

Abstract

We demonstrate that intersubband (ISB) polaritons are robust to inhomogeneous effects originating from the presence of multiple quantum wells (MQWs). In a series of samples that exhibit mid-infrared ISB absorption transitions with broadenings varying by a factor of 5 (from 4 meV to 20meV), we have observed polariton linewidths always lying in the 4 - 7 meV range only. We have experimentally verified the dominantly inhomogeneous origin of the broadening of the ISB transition, and that the linewidth reduction effect of the polariton modes persists up to room-temperature. This immunity to inhomogeneous broadening is a direct consequence of the coupling of the large number of ISB oscillators to a single photonic mode. It is a precious tool to gauge the natural linewidth of the ISB plasmon , that is otherwise masked in such MQWs system , and is also beneficial in view of perspective applications such as intersubband polariton lasers.

References in corpus (4)

• Ultra-Strong Light-Matter Coupling Regime with Polariton Dots
• Input-output theory of cavities in the ultra-strong coupling regime: the case of a time-independent vacuum Rabi frequency
• Octave-spanning semiconductor laser
• Inter-mode reactive coupling induced by waveguide-resonator interaction

Cited by in corpus (6)

• Molecular polaritonics: Chemical Dynamics under strong Light-Matter Coupling
• Strong light-matter coupling in MoS${}_2$
• A generalized Gross-Pitaevskii model for intersubband polariton lasing
• Light-matter interactions in the vacuum of ultra-strongly coupled systems
• Magnetic-field-induced cavity protection for intersubband polaritons
• Direct polariton-to-electron tunneling in quantum cascade detectors operating in the strong light-matter coupling regime