Coherence protection in coupled quantum systems

The interaction of a quantum system with its environment causes decoherence, setting a fundamental limit on its suitability for quantum information processing. However, we show that if the system consists of coupled parts with different internal energy scales then the interaction of one part with a thermal bath need not lead to loss of coherence from the other. Remarkably, we find that the protected part can remain coherent for longer when the coupling to the bath becomes stronger or the temperature is raised. Our theory will enable the design of decoherence-resistant hybrid quantum computers.

Citation

Cammack , H M , Kirton , P G , Stace , T , Eastham , P , Keeling , J M J & Lovett , B W 2018 , ' Coherence protection in coupled quantum systems ' , Physical Review. A, Atomic, molecular, and optical physics , vol. 97 , no. 2 , 022103 . https://doi.org/10.1103/PhysRevA.97.022103

Publication

Physical Review. A, Atomic, molecular, and optical physics

Status

Peer reviewed

DOI

https://doi.org/10.1103/PhysRevA.97.022103

ISSN

1050-2947

Type

Journal article

Rights

Copyright © 2018, American Physical Society. This work has been made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at https://doi.org/10.1103/PhysRevA.97.022103

Description

HMC acknowledges studentship funding from EPSRC under grant no. EP/G03673X/1. PGK acknowledges support from EPSRC (EP/M010910/1). BWL acknowledges support from EPSRC (EP/K025562/1). PRE acknowledges funding from SFI (15/IACA/3402). JK acknowledges financial support from EPSRC programs “TOPNES” (EP/I031014/1) and “Hybrid-Polaritonics” (EP/M025330/1).

Collections

University of St Andrews Research

URI

https://hdl.handle.net/10023/12588