Planar nanophotonic structures enable broadband, near-unity coupling of emission from quantum dots embedded within, thereby realizing ideal singe-photon sources. The efficiency and coherence of the single-photon source is limited by charge noise, which results in the broadening of the emission spectrum.We report suppression of the noise by fabricating photonic crystal waveguides in a gallium arsenide membrane containing quantum dots embedded in a p-i-n diode. Local electrical contacts in the vicinity of the waveguides minimize the leakage current and allow fast electrical control (≈4 MHz bandwidth) of the quantum dot resonances. Resonant linewidth measurements of 79 quantum dots coupled to the photonic crystal waveguides exhibit near transform-limited emission over a 6 nm wide range of emission wavelengths. Importantly, the local electrical contacts allow independent tuning of multiple quantum dots on the same chip, which together with the transform-limited emission are key components in realizing multiemitter-based quantum information processing.
@article{arxiv.2005.03943,
title = {Near Transform-limited Quantum Dot Linewidths in a Broadband Photonic Crystal Waveguide},
author = {Freja T. Pedersen and Ying Wang and Cecilie T. Olesen and Sven Scholz and Andreas D. Wieck and Arne Ludwig and Matthias C. Löbl and Richard J. Warburton and Leonardo Midolo and Ravitej Uppu and Peter Lodahl},
journal= {arXiv preprint arXiv:2005.03943},
year = {2020}
}