Nonlinear viscous vortex motion in two-dimensional Josephson-junction arrays

Journal Article · Fri Jul 01 00:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.1143· OSTI ID:7232907

Hagenaars, T J; Tiesinga, P H.E.; van Himbergen, J E ^[1]; Jose, J V ^[2]

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1. Instituut voor Theoretische Fysica, Princetonplein 5, Postbus 80006, 3508 TA Utrecht (Netherlands)
2. Instituut voor Theoretische Fysica, Princetonplein 5, Postbus 80006, 3508 TA Utrecht (Netherlands) Department of Physics, Northeastern University, Boston, Massachusetts 02115 (United States)

When a vortex in a two-dimensional Josephson-junction array is driven by a constant external current it may move as a particle in a viscous medium. Here we study the nature of this viscous motion. We model the junctions in a square array as resistively and capacitively shunted Josephson junctions and carry out numerical calculations of the current-voltage characteristics. We find that the current-voltage characteristics in the damped regime are well described by a model with a nonlinear viscous force of the form [ital F][sub [ital D]]=[eta]([ital [dot y]])[ital [dot y]]=[[ital A]/(1+[ital B][ital [dot y]]][ital [dot y]], where [ital [dot y]] is the vortex velocity, [eta]([ital [dot y]]) is the velocity-dependent viscosity, and [ital A] and [ital B] are constants for a fixed value of the Stewart-McCumber parameter. This result is found to apply also for triangular lattices in the overdamped regime. Further qualitative understanding of the nature of the nonlinear friction on the vortex motion is obtained from a graphic analysis of the microscopic vortex dynamics in the array. The consequences of having this type of nonlinear friction law are discussed and compared to previous theoretical and experimental studies.

• OSTI ID: 7232907
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:2; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665411* -- Basic Superconductivity Studies-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COMPUTERIZED SIMULATION
JOSEPHSON JUNCTIONS
JUNCTIONS
MAGNETIC FLUX
SIMULATION
SUPERCONDUCTING JUNCTIONS
SUPERCONDUCTORS
TWO-DIMENSIONAL CALCULATIONS
TYPE-II SUPERCONDUCTORS
VISCOSITY
VORTICES