Coherent coupling between localised and propagating phonon polaritons

TL;DR

This paper demonstrates coherent coupling between localized and propagating phonon polaritons in silicon carbide nano-resonators, enabling potential quantum circuit applications.

Contribution

It introduces a method to achieve phase-matching for coherent coupling by fabricating nano-resonators that serve dual functions.

Findings

Successful demonstration of phase-matched coherent coupling

Long-lived localized modes coupled with low-loss propagating modes

Potential for phonon-polariton based quantum circuits

Abstract

Following the recent observation of localised phonon polaritons in user-defined silicon carbide nano-resonators, here we demonstrate coherent coupling between those localised modes and propagating phonon polaritons bound to the surface of the nano-resonator's substrate. In order to obtain phase-matching, the nano-resonators have been fabricated to serve the double function of hosting the localised modes, while also acting as grating for the propagating ones. The coherent coupling between long lived, optically accessible localised modes, and low-loss propagative ones, opens the way to the design and realisation of phonon-polariton based quantum circuits.