A single quantum dot in a microcavity produces indistinguishable photons for quantum devices
A new ultrabright source of single photons that is 20 times brighter than commonly used sources, and which emits photons that are 99.5% indistinguishable from one another, has been developed by researchers from the CNRS-LPN Laboratoire de Photonique et de Nanostructures, Université Paris-Saclay (Marcoussis, France), the University of Queensland (Brisbane, Australia), Université Grenoble Alpes (Grenoble, France), CNRS, Institut Néel (Grenoble, France), Université Paris Diderot (Paris, France), and Ecole Polytechnique, Université Paris-Saclay (Palaiseau, France).1
This feat was achieved thanks to the nanometrically precise positioning of a single quantum dot within an optical microcavity. Adding an electrical bias to the device helped reduce the "noise" around the quantum dot, which generally renders photons different from one another.
The results make it possible to conduct quantum computing of unprecedented complexity, a first step toward the creation of optical quantum computers.
Source: http://www.alphagalileo.org/ViewItem.aspx?ItemId=161714&CultureCode=en
REFERENCE:
1. Niccolo Somaschi et al., Nature Photonics (2016); doi:10.1038/Nphoton.2016.23
John Wallace | Senior Technical Editor (1998-2022)
John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.