Experimental reconstruction of the few-photon nonlinear scattering matrix from a single quantum dot in a nanophotonic waveguide

TL;DR

This paper experimentally reconstructs the scattering matrix of few-photon interactions with a quantum dot in a nanophotonic waveguide, revealing complex nonlinear photon physics crucial for quantum information processing.

Contribution

It demonstrates a method to directly measure the nonlinear scattering matrix of a quantum dot coupled to a waveguide using few-photon transport experiments.

Findings

Reconstructed 1- and 2-photon scattering matrix elements

Provided insights into many-body nonlinear photon interactions

Validated the approach with experimental data

Abstract

Coherent photon-emitter interfaces offer a way to mediate efficient nonlinear photon-photon interactions, much needed for quantum information processing. Here we experimentally study the case of a two-level emitter, a quantum dot, coupled to a single optical mode in a nanophotonic waveguide. We carry out few-photon transport experiments and record the statistics of the light to reconstruct the scattering matrix elements of 1- and 2-photon components. This provides direct insight to the complex nonlinear photon interaction that contains rich many-body physics.