Cryogenic spectroscopy of ultra-low density colloidal lead chalcogenide quantum dots on chip-scale optical cavities towards single quantum dot near-infrared cavity QED

TL;DR

This paper demonstrates cavity quantum electrodynamics with ultra-low density lead chalcogenide quantum dots on silicon optical cavities, showing strong emission modifications and saturation effects at near-infrared wavelengths for quantum information applications.

Contribution

It provides the first evidence of single-dot level cavity QED with sparse Pb-chalcogenide nanocrystals on chip-scale silicon cavities at near-infrared wavelengths.

Findings

Large emission enhancements observed.

Strong emission modifications achieved.

Saturation spectroscopy at 77K demonstrates modified nanocrystal dynamics.

Abstract

We present evidence of cavity quantum electrodynamics from a sparse density of strongly quantum-confined Pb-chalcogenide nanocrystals (between 1 and 10) approaching single-dot levels on moderately high-Q mesoscopic silicon optical cavities. Operating at important near-infrared (1500-nm) wavelengths, large enhancements are observed from devices and strong modifications of the QD emission are achieved. Saturation spectroscopy of coupled QDs is observed at 77K, highlighting the modified nanocrystal dynamics for quantum information processing.