Superconducting phase qubit coupled to a nanomechanical resonator: Beyond the rotating-wave approximation

Journal Article · Mon Nov 01 04:00:00 EST 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.70.052315· OSTI ID:20646191

Sornborger, Andrew T ^[1]; Cleland, Andrew N ^[2]; Geller, Michael R ^[3]

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1. Department of Mathematics, University of Georgia, Athens, Georgia 30602-2451 (United States)
2. Department of Physics, University of California, Santa Barbara, California 93106 (United States)
3. Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602-2451 (United States)

We consider a simple model of a Josephson junction phase qubit coupled to a solid-state nanoelectromechanical resonator. This and many related qubit-resonator models are analogous to an atom in an electromagnetic cavity. When the systems are weakly coupled and nearly resonant, the dynamics is accurately described by the rotating-wave approximation (RWA) or the Jaynes-Cummings model of quantum optics. However, the desire to develop faster quantum-information-processing protocols necessitates approximate, yet analytic descriptions that are valid for more strongly coupled qubit-resonator systems. Here we present a simple theoretical technique, using a basis of dressed states, to perturbatively account for the leading-order corrections to the RWA. By comparison with exact numerical results, we demonstrate that the method is accurate for moderately strong coupling and provides a useful theoretical tool for describing fast quantum information processing. The method applies to any quantum two-level system linearly coupled to a harmonic oscillator or single-mode boson field.

• OSTI ID: 20646191
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 5 Vol. 70; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
ATOMS
BOSONS
COMPARATIVE EVALUATIONS
CORRECTIONS
DATA PROCESSING
HARMONIC OSCILLATORS
INFORMATION THEORY
JOSEPHSON JUNCTIONS
OPTICS
QUANTUM MECHANICS
RESONATORS
SQUID DEVICES