An electrically pumped phonon-polariton laser

TL;DR

This paper introduces an electrically pumped device that emits coherent phonon polaritons, combining photons and phonons, with potential applications in mid-infrared photonics and quantum technologies.

Contribution

It demonstrates the first electrically pumped phonon-polariton laser using a quantum cascade structure at 26.3 μm.

Findings

Achieved coherent phonon-polariton emission near the optical phonon energy.

Observed Stokes and anti-Stokes components in Raman spectrum.

Polariton mode has a 65% phonon fraction.

Abstract

We report a device that provides coherent emission of phonon polaritons, a mixed state between photons and optical phonons in an ionic crystal. An electrically pumped GaInAs/AlInAs quantum cascade structure provides intersubband gain into the polariton mode at = 26.3 \mu m, allowing self-oscillations close to the longitudinal optical phonon energy of AlAs. Because of the large computed phonon fraction of the polariton of 65%, the emission appears directly on a Raman spectrum measurement exhibiting a Stokes and anti-Stokes component with the expected shift of 48 meV.