Quantum registers hit the right wavelength

UCLQ researcher Dr Siddharth Dhomkar and UCLQ Director Prof John Morton write in a recent Nature Materials News and Views article:

"Controlling nuclear spins coupled to an electron spin in silicon carbide has enabled development of a ‘quantum register’ interfaced with telecom photons, leading to the possibility of distant transport of quantum information.

The control of impurities in optical fibres has enabled the ultralow-loss transmission of near-infrared (NIR) light that underpins our ability to share vast quantities of data around the world. Such optical communication channels are already being upgraded to possess in-built security enshrined by the laws of quantum mechanics, but only over short point-to-point connections. Quantum interfaces that can connect light to matter-based registers of quantum bits (used to generate and purify quantum entanglement among distant sites) are required to allow fundamentally secure optical communication over the long distances required for widespread impact. In this context, carefully selected optical impurities can play a role¹. Writing in Nature Materials, Alexandre Bourassa and colleagues² demonstrate exceptional control of a register of electron and nuclear spins associated with the divacancy (VV) defect in silicon carbide (SiC), firmly establishing it as an attractive system for the development of optical quantum networks..."

Read the full article at Nature Materials.