Probing noise in flux qubits via macroscopic resonant tunneling

R. Harris, M. W. Johnson, S. Han, A. J. Berkley, J. Johansson, P. Bunyk, E. Ladizinsky, S. Govorkov, M. C. Thom, S. Uchaikin, B. Bumble, A. Fung, A. Kaul, A. Kleinsasser, M. H S Amin, D. V. Averin

Division for Electronic Engineering

Research output: Contribution to journal › Article

49 Citations (Scopus)

Abstract

Macroscopic resonant tunneling between the two lowest lying states of a bistable rf SQUID is used to characterize noise in a flux qubit. Measurements of the incoherent decay rate as a function of flux bias revealed a Gaussian-shaped profile that is not peaked at the resonance point but is shifted to a bias at which the initial well is higher than the target well. The rms amplitude of the noise, which is proportional to the dephasing rate 1/τφ, was observed to be weakly dependent on temperature below 70mK. Analysis of these results indicates that the dominant source of low energy flux noise in this device is a quantum mechanical environment in thermal equilibrium.

Original language	English
Article number	117003
Journal	Physical Review Letters
Volume	101
Issue number	11
DOIs	https://doi.org/10.1103/PhysRevLett.101.117003
Publication status	Published - 10 Sep 2008

ASJC Scopus subject areas

Physics and Astronomy(all)

Access to Document

10.1103/PhysRevLett.101.117003

Fingerprint Dive into the research topics of 'Probing noise in flux qubits via macroscopic resonant tunneling'. Together they form a unique fingerprint.

Cite this

Harris, R., Johnson, M. W., Han, S., Berkley, A. J., Johansson, J., Bunyk, P., Ladizinsky, E., Govorkov, S., Thom, M. C., Uchaikin, S., Bumble, B., Fung, A., Kaul, A., Kleinsasser, A., Amin, M. H. S., & Averin, D. V. (2008). Probing noise in flux qubits via macroscopic resonant tunneling. Physical Review Letters, 101(11), [117003]. https://doi.org/10.1103/PhysRevLett.101.117003

Probing noise in flux qubits via macroscopic resonant tunneling. / Harris, R.; Johnson, M. W.; Han, S.; Berkley, A. J.; Johansson, J.; Bunyk, P.; Ladizinsky, E.; Govorkov, S.; Thom, M. C.; Uchaikin, S.; Bumble, B.; Fung, A.; Kaul, A.; Kleinsasser, A.; Amin, M. H S; Averin, D. V.

In: Physical Review Letters, Vol. 101, No. 11, 117003, 10.09.2008.

Research output: Contribution to journal › Article

@article{10b824ace34948c6b54547d75ab9b974,

title = "Probing noise in flux qubits via macroscopic resonant tunneling",

abstract = "Macroscopic resonant tunneling between the two lowest lying states of a bistable rf SQUID is used to characterize noise in a flux qubit. Measurements of the incoherent decay rate as a function of flux bias revealed a Gaussian-shaped profile that is not peaked at the resonance point but is shifted to a bias at which the initial well is higher than the target well. The rms amplitude of the noise, which is proportional to the dephasing rate 1/τφ, was observed to be weakly dependent on temperature below 70mK. Analysis of these results indicates that the dominant source of low energy flux noise in this device is a quantum mechanical environment in thermal equilibrium.",

author = "R. Harris and Johnson, {M. W.} and S. Han and Berkley, {A. J.} and J. Johansson and P. Bunyk and E. Ladizinsky and S. Govorkov and Thom, {M. C.} and S. Uchaikin and B. Bumble and A. Fung and A. Kaul and A. Kleinsasser and Amin, {M. H S} and Averin, {D. V.}",

year = "2008",

month = sep,

day = "10",

doi = "10.1103/PhysRevLett.101.117003",

language = "English",

volume = "101",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "11",

}

TY - JOUR

T1 - Probing noise in flux qubits via macroscopic resonant tunneling

AU - Harris, R.

AU - Johnson, M. W.

AU - Han, S.

AU - Berkley, A. J.

AU - Johansson, J.

AU - Bunyk, P.

AU - Ladizinsky, E.

AU - Govorkov, S.

AU - Thom, M. C.

AU - Uchaikin, S.

AU - Bumble, B.

AU - Fung, A.

AU - Kaul, A.

AU - Kleinsasser, A.

AU - Amin, M. H S

AU - Averin, D. V.

PY - 2008/9/10

Y1 - 2008/9/10

N2 - Macroscopic resonant tunneling between the two lowest lying states of a bistable rf SQUID is used to characterize noise in a flux qubit. Measurements of the incoherent decay rate as a function of flux bias revealed a Gaussian-shaped profile that is not peaked at the resonance point but is shifted to a bias at which the initial well is higher than the target well. The rms amplitude of the noise, which is proportional to the dephasing rate 1/τφ, was observed to be weakly dependent on temperature below 70mK. Analysis of these results indicates that the dominant source of low energy flux noise in this device is a quantum mechanical environment in thermal equilibrium.

AB - Macroscopic resonant tunneling between the two lowest lying states of a bistable rf SQUID is used to characterize noise in a flux qubit. Measurements of the incoherent decay rate as a function of flux bias revealed a Gaussian-shaped profile that is not peaked at the resonance point but is shifted to a bias at which the initial well is higher than the target well. The rms amplitude of the noise, which is proportional to the dephasing rate 1/τφ, was observed to be weakly dependent on temperature below 70mK. Analysis of these results indicates that the dominant source of low energy flux noise in this device is a quantum mechanical environment in thermal equilibrium.

UR - http://www.scopus.com/inward/record.url?scp=51749104144&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=51749104144&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.101.117003

DO - 10.1103/PhysRevLett.101.117003

M3 - Article

AN - SCOPUS:51749104144

VL - 101

JO - Physical Review Letters

JF - Physical Review Letters

SN - 0031-9007

IS - 11

M1 - 117003

ER -