Intersubband polaritonics revisited

TL;DR

This paper revisits intersubband polaritonics, revealing that Coulomb interactions are essential and fundamentally alter the nature of light-matter coupling, showing polaritons as collective excitations rather than non-interacting pairs.

Contribution

It demonstrates that Coulomb interactions are crucial in intersubband polariton systems, fundamentally changing the understanding of their elementary excitations and light-matter coupling mechanisms.

Findings

Coulomb interactions significantly influence intersubband polariton behavior.

Intersubband polaritons are collective excitations, not simple electron-hole pairs.

The nature of light-matter coupling in these systems is fundamentally altered.

Abstract

We revisited the intersubband polaritonics - the branch of mesoscopic physics having a huge potential for optoelectronic applications in the infrared and terahertz domains - and found that, contrary to the general opinion, the Coulomb interactions play crucial role in the processes of light-matter coupling in the considered systems. Electron-electron and electron-hole interactions radically change the nature of the elementary excitations in these systems. We show that intersubband polaritons represent the result of the coupling of a photonic mode with collective excitations, and not non-interacting electron-hole pairs as it was supposed in the previous works on the subject.