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Mechanically Detecting and Avoiding the Quantum Fluctuations of a Microwave Field

Suh, J. and Weinstein, A. J. and Lei, C. U. and Wollman, E. E. and Steinke, S. K. and Meystre, P. and Clerk, A. A. and Schwab, K. C. (2014) Mechanically Detecting and Avoiding the Quantum Fluctuations of a Microwave Field. Science, 344 (6189). pp. 1262-1265. ISSN 0036-8075. doi:10.1126/science.1253258.

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Quantum fluctuations of the light field used for continuous position detection produces stochastic back-action forces and ultimately limits the sensitivity. To overcome this limit, the back-action forces can be avoided by giving up complete knowledge of the motion, and these types of measurements are called “back-action evading” or “quantum nondemolition” detection. We present continuous two-tone back-action evading measurements with a superconducting electromechanical device, realizing three long-standing goals: detection of back-action forces due to the quantum noise of a microwave field, reduction of this quantum back-action noise by 8.5 ± 0.4 dB, and measurement imprecision of a single quadrature of motion 2.4 ± 0.7 dB below the mechanical zero-point fluctuations. Measurements of this type will find utility in ultrasensitive measurements of weak forces and nonclassical states of motion.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Suh, J.0000-0002-0112-0499
Weinstein, A. J.0000-0002-2354-0777
Wollman, E. E.0000-0002-5474-3745
Clerk, A. A.0000-0001-7297-9068
Schwab, K. C.0000-0001-8216-4815
Additional Information:© 2014 American Association for the Advancement of Science. Received 12 March 2014; accepted 2 May 2014 Published online 15 May 2014. We would like to acknowledge J. Hertzberg, T. Rocheleau, T. Ndukum, and M. Shaw for work on earlier experiments that led to these results. This work is supported by funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation (NSF-IQIM 1125565), by DARPA (DARPA-QUANTUM HR0011-10-1-0066), and by NSF (NSF-DMR 1052647, NSF-EEC 0832819).
Group:Kavli Nanoscience Institute, Institute for Quantum Information and Matter
Funding AgencyGrant Number
Gordon and Betty Moore FoundationUNSPECIFIED
Institute for Quantum Information and Matter (IQIM)UNSPECIFIED
Defense Advanced Research Projects Agency (DARPA)HR0011-10-1-0066
Issue or Number:6189
Record Number:CaltechAUTHORS:20140515-115038262
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45767
Deposited By: Joy Painter
Deposited On:15 May 2014 20:05
Last Modified:10 Nov 2021 17:16

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