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Defect Motion and Lattice Pinning Barrier in Josephson-Junction Ladders

H. Kang·Jong Soo Lim·J. -Y. Fortin·J. Choi·M. Y. Choi
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Abstract

We study motion of domain wall defects in a fully frustrated Josephson-unction ladder system, driven by small applied currents. For small system sizes, the energy barrier E_B to the defect motion is computed analytically via symmetry and topological considerations. More generally, we perform numerical simulations directly on the equations of motion, based on the resistively-shunted junction model, to study the dynamics of defects, varying the system size. Coherent motion of domain walls is observed for large system sizes. In the thermodynamical limit, we find E_B=0.1827 in units of the Josephson coupling energy.

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H. Kang, Jong Soo Lim, J. -Y. Fortin, J. Choi, M. Y. Choi. 2005-12-05. Defect Motion and Lattice Pinning Barrier in Josephson-Junction Ladders. https://doi.org/10.1103/physrevb.73.014504

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