SearcharxivSearch

arXiv subjects

W. Maluf

Publications and source records attributed to W. Maluf.

2 recordsLinked to original sources

On the origin of reentrance in 2D Josephson Junction Arrays

A comparative study of the magnetic properties of shunted and unshunted two-dimensional Josephson junction arrays (2D-JJA) is presented. Using a single-plaquette approximation of the 2D-JJA model, we were able to successfully fit all our experimental data (for the temperature, AC and DC field dependencies of susceptibility) and demonstrate that the dynamic reentrance of AC susceptibility is directly linked to the value of the Stewart-McCumber parameter β_C. Based on extensive numerical simulations, a phase diagram β_C vs β_L is plotted which demarcates the border between the reentrant and non-reentrant behavior in the arrays.

cond-mat.supr-con

Influence of nonuniform critical current density profile on magnetic field behavior of AC susceptibility in 2D Josephson Junction Arrays

Employing mutual-inductance measurements we study the magnetic field dependence of complex AC susceptibility of artificially prepared highly ordered (periodic) two-dimensional Josephson junction arrays of unshunted Nb-AlO_x-Nb junctions. The observed behavior can be explained assuming single-plaquette approximation of the overdamped model with an inhomogeneous critical current distribution within a single junction.

cond-mat.supr-con