# Coherent Single Photon Emission from Colloidal Lead Halide Perovskite Quantum Dots

## TL;DR

This paper demonstrates that colloidal lead halide perovskite quantum dots can serve as efficient, coherent single-photon emitters with potential applications in quantum photonics, overcoming previous incoherence issues.

## Contribution

It shows that PQDs exhibit highly efficient, coherent single-photon emission with long coherence times, paving the way for their use in quantum information technologies.

## Key findings

- Single photon emission with 80 ps coherence time
- Emission efficiency suitable for quantum applications
- Potential for integration with nano-photonics

## Abstract

Chemically prepared colloidal semiconductor quantum dots have long been proposed as scalable and color-tunable single emitters in quantum optics, but they have typically suffered from prohibitively incoherent emission. We now demonstrate that individual colloidal lead halide perovskite quantum dots (PQDs) display highly efficient single photon emission with optical coherence times as long as 80 ps, an appreciable fraction of their 210 ps radiative lifetimes. These measurements suggest that PQDs should be explored as building blocks in sources of indistinguishable single photons and entangled photon pairs. Our results present a starting point for the rational design of lead halide perovskite-based quantum emitters with fast emission, wide spectral-tunability, scalable production, and which benefit from the hybrid-integration with nano-photonic components that has been demonstrated for colloidal materials.

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Source: https://tomesphere.com/paper/1812.11923