Quantum thermometry using the ac Stark shift within the Rabi model
Abstract
A quantum two-level system coupled to a harmonic oscillator represents a ubiquitous physical system. New experiments in circuit QED and nanoelectromechanical systems (NEMS) achieve unprecedented coupling strength at large detuning between qubit and oscillator, thus requiring a theoretical treatment beyond the Jaynes-Cummings model. Here we present a new method for describing the qubit dynamics in this regime, based on an oscillator correlation function expansion of a non-Markovian master equation in the polaron frame. Our technique yields a new numerical method as well as a succinct approximate expression for the qubit dynamics. These expressions are valid in the experimentally interesting regime of strong coupling at low temperature. We obtain a new expression for the ac Stark shift and show that this enables practical and precise qubit thermometry of an oscillator.
Citation
Higgins , K D B , Lovett , B W & Gauger , E M 2013 , ' Quantum thermometry using the ac Stark shift within the Rabi model ' , Physical Review. B, Condensed matter and materials physics , vol. 88 , no. 15 , 155409 . https://doi.org/10.1103/PhysRevB.88.155409
Publication
Physical Review. B, Condensed matter and materials physics
Status
Peer reviewed
ISSN
1098-0121Type
Journal article
Rights
© 2013. American Physical Society.
Description
This work was supported by the EPSRC, the National Research Foundation and Ministry of Education, Singapore, and the Royal Society.Collections
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