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Title: High-fidelity measurement and quantum feedback control in circuit QED

Abstract

Circuit QED is a promising solid-state quantum computing architecture. It also has excellent potential as a platform for quantum control--especially quantum feedback control--experiments. However, the current scheme for measurement in circuit QED is low efficiency and has low signal-to-noise ratio for single-shot measurements. The low quality of this measurement makes the implementation of feedback difficult, and here we propose two schemes for measurement in circuit QED architectures that can significantly improve signal-to-noise ratio and potentially achieve quantum-limited measurement. Such measurements would enable the implementation of quantum feedback protocols and we illustrate this with a simple entanglement-stabilization scheme.

Authors:
;  [1];  [2];  [3]
  1. Centre for Quantum Computer Technology and School of Physical Sciences, University of Queensland, St Lucia, Queensland 4072 (Australia)
  2. Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)
  3. Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS34 8QZ (United Kingdom)
Publication Date:
OSTI Identifier:
20786290
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.062327; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CONTROL; EFFICIENCY; FEEDBACK; QUANTUM COMPUTERS; QUANTUM ELECTRODYNAMICS; QUANTUM ENTANGLEMENT; SIGNAL-TO-NOISE RATIO; STABILIZATION

Citation Formats

Sarovar, Mohan, Milburn, G. J., Goan, H.-S., and Spiller, T. P. High-fidelity measurement and quantum feedback control in circuit QED. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Sarovar, Mohan, Milburn, G. J., Goan, H.-S., & Spiller, T. P. High-fidelity measurement and quantum feedback control in circuit QED. United States. doi:10.1103/PHYSREVA.72.0.
Sarovar, Mohan, Milburn, G. J., Goan, H.-S., and Spiller, T. P. Thu . "High-fidelity measurement and quantum feedback control in circuit QED". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786290,
title = {High-fidelity measurement and quantum feedback control in circuit QED},
author = {Sarovar, Mohan and Milburn, G. J. and Goan, H.-S. and Spiller, T. P.},
abstractNote = {Circuit QED is a promising solid-state quantum computing architecture. It also has excellent potential as a platform for quantum control--especially quantum feedback control--experiments. However, the current scheme for measurement in circuit QED is low efficiency and has low signal-to-noise ratio for single-shot measurements. The low quality of this measurement makes the implementation of feedback difficult, and here we propose two schemes for measurement in circuit QED architectures that can significantly improve signal-to-noise ratio and potentially achieve quantum-limited measurement. Such measurements would enable the implementation of quantum feedback protocols and we illustrate this with a simple entanglement-stabilization scheme.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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