Équipe de Recherche en Physique de l'Information Quantique


author = {S. M. Anton, C. Mueller, J. S. Birenbaum, S. R. O'Kelley, A. D. Fefferman, D. S. Golubev, G. C. Hilton, H.-M. Cho, K. D. Irwin, F. C. Wellstood, G. Schon, A. Shnirman, and J. Clarke},
title = {Pure dephasing in flux qubits due to flux noise with spectral density scaling as {\$}1/ f^α{\$}},
journal = {Physical Review B},
year = {2012},
volume = {85},
number = {22},
pages = {224505},
month = {jun},
doi = {10.1103/PhysRevB.85.224505},
abstract = {Magnetic flux noise is a source of pure dephasing in superconducting flux qubits. Measurements on dc Superconducting QUantum Interference Devices over a range of temperatures show that the flux noise spectral density is {\$}A^2/(f/1 \hbox{Hz})^\alpha{\$}, where {\$}A{\$} is of the order of 1 {\$}\mu\Phi{\_}0 \, \hbox{Hz}^{-1/2}{\$} and {\$}0.61 \leq \alpha \leq 0.95{\$}; {\$}\Phi{\_}{0}{\$} is the flux quantum. For a qubit with an energy level splitting linearly coupled to the applied flux, calculations of the dependence of the pure dephasing time {\$}\tau{\_}\phi{\$} on {\$}\alpha{\$} for fixed {\$}A{\$} show that {\$}\tau{\_}\phi{\$} decreases rapidly as {\$}\alpha{\$} is reduced. We present numerical values of {\$}\tau{\_}\phi{\$} for the measured values of {\$}A{\$} and {\$}\alpha{\$}.},
url = {http://prb.aps.org/abstract/PRB/v85/i22/e224505},
eprint = {1111.7272},
local-url = {PureDephasing.pdf}}