COLLOQUIUM 2022

Shedding Light on Spins: Through the looking-glass, and what we found there

SpeakerProf. Mete Atatüre, Cavendish Laboratory, University of Cambridge
HostsAnjan Soumyanarayanan, Lee Ching Hua
DateThu, 9 Jun @ 4.30–5.30 PM
Zoom registration linkhttps://nus-sg.zoom.us/webinar/register/WN_66jmbElUReqeJmJ9M9qtfA

Abstract

Optically active spins in solids are often considered prime candidates for scalable and feasible quantum-optical devices. Numerous material platforms including diamond, semiconductors, and atomically thin 2d materials are investigated, where each platform brings their own advantages along with their challenges. Semiconductor quantum dots are the current state-of-the-art for optical properties such as tuneability, brightness and indistinguishability. Their nickname “artificial atom” was coined historically to highlight how similar they can be to isolated single atoms, but in fact they are far from the realisation of a simple two-level system. The inherently mesoscopic nature of a quantum dot leads to a multitude of dynamics between spins, charges, vibrations, and light.

In particular, it offers a unique realisation of a tripartite interface between light, a single proxy qubit (electron spin) and an isolated spin ensemble (nuclei). Ability to control these constituents and their mutual interactions creates opportunities to realise an optically controllable ensemble of ~50,000 spins. In this talk, I will present the decade-long journey from treating the quantum dot nuclei as noise to the observation of their collective magnon modes and eventually to their tuneable quantum correlations, all witnessed via a single electron spin driven by light.

Biography

Mete Atatüre received his PhD from Boston University Quantum Imaging Laboratory in 2002 on multi-parameter entanglement and then joined the Quantum Photonics Group at ETH Zurich as a postdoctoral fellow. Since 2007, he has been a faculty member at the Cavendish Laboratory in Cambridge and as full professor since 2015. His research efforts include optical control of spin-photon interfaces in solids, development of nanoscale quantum sensors and investigations of novel quantum materials and devices. He is a Fellow of the Institute of Physics, the Optical Society of America, the Turkish Science Academy and Academia Europaea.