Nonlinear chiral quantum optics with giant-emitter pairs

TL;DR

This paper introduces a novel setup combining giant emitters with nonlinear quantum optics to achieve tunable, directional multiphoton emission, enabling advanced quantum network components with correlated photons.

Contribution

It presents a new mechanism for multiphoton chiral emission using giant emitters and nonlinear interactions, offering tunable directionality and potential for quantum network applications.

Findings

Demonstrates destructive interference in one propagation direction

Shows tunable chirality via coupling phases

Proposes use as a building block for chiral quantum networks

Abstract

We propose a setup which combines giant emitters (coupling to light at multiple points separated by wavelength distances) with nonlinear quantum optics and its correlated photons. In this setup, we reveal a mechanism for multiphoton chiral emission: the propagation phase of the center of mass of two strongly correlated photons (a doublon), and the phases encoded in the coupling points of two giant emitters, can yield completely destructive interference in one propagation direction while supporting emission in the other direction. The degree of chirality can be tuned by the phases of the couplings. We show that the proposed setup can provide directional quantum many-body resources, and can be configured as a building block for a chiral quantum network with ``correlated flying qubits'', enabling distinct applications beyond linear chiral setups. Our findings point toward a rich landscape of tailoring multiphoton propagation and correlation properties by exploiting interference effects of giant emitters coupling to nonlinear photonic baths.