title: Quantum fluctuations in Josephson junction comparators.
abstract: We have developed a method for calculation of quantum fluctuation effects, in particular, of the uncertainty zone developing at the potential curvature sign inversion, for a damped harmonic oscillator with arbitrary time dependence of frequency and for arbitrary temperature, within the Caldeira-Leggett model. The method has been applied to the calculation of the gray zone width Delta Ix of Josephson-junction balanced comparators. The calculated temperature dependence of Delta Ix in the range 1.5 to 4.2 K is in virtually perfect agreement with experimental data for Nb-trilayer comparators with critical current densities of 1.0 and 5.5 kA/cm2, without any fitting parameters.
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11974-3800, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Walls
authors.forename: Timur V
authors.initials: TV
authors.lastname: Filippov
authors.forename: Konstantin K
authors.initials: KK
authors.lastname: Likharev