Effect of thermal phase fluctuations on the inductances of Josephson junctions, arrays of junctions, and superconducting films
- Department of Physics, Ohio State University, Columbus, Ohio 43210-1106 (United States)
We calculate the factor by which thermal phase fluctuations, as distinct from phase-slip fluctuations, increase the inductance L{sub J} of a resistively shunted Josephson junction (JJ) above its mean-field value L{sub 0}. We find that quantum mechanics suppresses fluctuations when T drops below a temperature, T{sub Q}=({Dirac_h}/2{pi})/k{sub B}GL{sub 0}, where G is the shunt conductance. Examination of the calculated sheet inductance L{sub A}(T)/L{sub 0}(T) of arrays of JJ's reveals that two-dimensional (2D) interconnections halve fluctuation effects, while reducing phase-slip effects by a much larger factor. Guided by these results, we calculate the sheet inductance L{sub F}(T)/L{sub 0}(T) of 2D films by treating each plasma oscillation mode as an overdamped JJ. In disordered s-wave superconductors, quantum suppression is important for L{sub F}(0)/L{sub F}(T)>0.14 (or T/T{sub C0}<0.94). In optimally doped YBCO and BSCCO quantum suppression is important for {lambda}{sup 2}(0)/{lambda}{sup 2}(T)>0.25, where {lambda} is the penetration depth. (c) 2000 The American Physical Society.
- OSTI ID:
- 20215097
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 61, Issue 2; Other Information: PBD: 1 Jan 2000; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
Similar Records
Kinetic inductance of Josephson-junction arrays: Dynamic and equilibrium calculations
Temperature scales of magnetization oscillations in an asymmetric quantum dot