Anderson Localization with Single Photons from a Quantum Emitter

TL;DR

This paper demonstrates Anderson localization of single photons emitted by a quantum emitter in disordered waveguides at room temperature, combining experimental results with a theoretical framework.

Contribution

It provides the first experimental demonstration of Anderson localization with single photons from a quantum emitter and develops a theoretical model for wave propagation in disordered systems.

Findings

Single photons undergo pronounced Anderson localization in disordered waveguides.

The stationary output intensity profile exhibits an inverse-variance scaling with disorder strength.

Room-temperature defect-based emitters are practical for studying Anderson localization in integrated photonics.

Abstract

Anderson localization of light is a fundamental emergent phenomenon in disordered systems. In arrays of coupled waveguides, it suppresses transport and causes photons to remain localized near the excitation site as coupling disorder increases. Here, we experimentally demonstrate Anderson localization using single photons emitted by a single-photon emitter in hexagonal boron nitride at room temperature. Despite the limited temporal coherence of the emitter, the photons undergo pronounced Anderson localization, evidenced by exponentially localized output intensity profiles in disordered waveguide lattices. Beyond the experimental demonstration, we develop a general theoretical framework for wave propagation in disordered tight-binding systems, showing that the configuration-averaged output intensity converges to a stationary spatial distribution at large propagation distances. In the case of off-diagonal disorder, this stationary profile is characterized by an effective localization length that exhibits a robust inverse-variance scaling with the disorder strength. These results establish defect-based room-temperature emitters as practical platforms for studying Anderson localization in integrated photonics and support their use in applications that exploit controlled disorder, including neuromorphic and quantum photonic architectures.