Experimental realization of highly-efficient broadband coupling of single quantum dots to a photonic crystal waveguide

TL;DR

This paper demonstrates highly efficient broadband coupling of single quantum dots to photonic crystal waveguides, achieving significant emission rate enhancement and large operational bandwidth, advancing single-photon source technology.

Contribution

It provides the first experimental realization of broadband, highly efficient quantum dot coupling to photonic crystal waveguides with high beta-factors and large bandwidths.

Findings

Quantum dots decay up to 27 times faster when coupled

Beta-factors up to 0.89 achieved

Bandwidth of 20 nm demonstrated

Abstract

We present time-resolved spontaneous emission measurements of single quantum dots embedded in photonic crystal waveguides. Quantum dots that couple to the photonic crystal waveguide are found to decay up to 27 times faster than uncoupled quantum dots. From these measurements $\beta$-factors of up to 0.89 are derived, and an unprecedented large bandwidth of 20 nm is demonstrated. This shows the promising potential of photonic crystal waveguides for efficient single-photon sources. The scaled frequency where the enhancement is observed is in excellent agreement with theory taking into account that the light-matter coupling is strongly enhanced due to the significant slow-down of light in the photonic crystal waveguide.