Environment-assisted quantum control of a solid-state spin via coherent dark states


Type
Article
Change log
Authors
Hansom, J 
Schulte, CHH 
Matthiesen, C 
Clarke, E 
Abstract

Understanding the interplay between a quantum system and its environment lies at the heart of quantum science and its applications. So far most efforts have focused on circumventing decoherence induced by the environment by either protecting the system from the associated noise or by manipulating the environment directly. Recently, parallel efforts using the environment as a resource have emerged, which could enable dissipation-driven quantum computation and coupling of distant quantum bits. Here, we realize the optical control of a semiconductor quantum-dot spin by relying on its interaction with an adiabatically evolving spin environment. The emergence of hyperfine-induced, quasi-static optical selection rules enables the optical generation of coherent spin dark states without an external magnetic field. We show that the phase and amplitude of the lasers implement multi-axis manipulation of the basis spanned by the dark and bright states, enabling control via projection into a spin-superposition state. Our approach can be extended, within the scope of quantum control and feedback, to other systems interacting with an adiabatically evolving environment.

Description
Keywords
quant-ph, quant-ph, cond-mat.mes-hall
Journal Title
Nature Physics
Conference Name
Journal ISSN
1745-2473
1745-2481
Volume Title
10
Publisher
Springer Science and Business Media LLC
Rights
All rights reserved
Sponsorship
European Research Council (617985)
We gratefully acknowledge financial support by the University of Cambridge, the European Research Council ERC Consolidator Grant agreement no. 617985, EU-FP7 Marie Curie Initial Training Network S3NANO, the NSF-funded Physics Frontier Center at the Joint Quantum Institute, and ARO MURI award no. W911NF0910406. T