arXiv subjects

A. van Otterlo

Publications and source records attributed to A. van Otterlo.

3 recordsLinked to original sources

arXiv1999

Quantum Fluctuations and Dissipation in Thin Superconducting Wires

We investigate quantum fluctuations in thin superconducting wires. We demonstrate that quantum phase slips dominate the system behavior at low temperatures and are well in the measurable range for sufficiently thin wires. We discuss the effect of dissipation, predict a new quantum superconductor-to-metal (insulator) phase transitions for wires with thicknesses in the 10-nm range, evaluate the resistance R(T) of such wires and compare our results with recent experimental findings.

cond-mat.mes-hall↗

arXiv1999

Vortices Freeze like Window Glass: the Vortex Molasses Scenario

We overview several recent experimental and numerical observations, which are at odds with the Vortex Glass theory of the freezing of disordered vortex matter. To reinvestigate the issue, we performed numerical simulations of the overdamped London - Langevin model, and use finite size scaling to analyze the data. Upon approaching the transition the initial Vortex Glass type criticality is arrested at some crossover temperature. Below this temperature the timescales continue growing very quickly, consistent with the Vogel-Fulcher form, while the spatial correlation length xi stops exhibiting any observable divergence. We call this mode of freezing the Vortex Molasses scenario.

cond-mat.supr-con↗

arXiv1994

Tunnel junctions of unconventional superconductors

The phenomenology of Josephson tunnel junctions between unconventional superconductors is developed further. In contrast to s-wave superconductors, for d-wave superconductors the direction dependence of the tunnel matrix elements that describe the barrier is relevant. We find the full I-V characteristics and comment on the thermodynamical properties of these junctions. They depend sensitively on the relative orientation of the superconductors. The I-V characteristics differ from the normal s-wave RSJ-like behavior.

cond-mat↗