Temperature and magnetic field dependence of the voltage in GaAs films with superconducting Ga grains

B. L. Willems; D. M.J. Taylor; J. Fritzsche; M. Malfait; J. Vanacken; V. V. Moshchalkov; E. Montoya; G. Van Tendeloo

doi:10.1140/epjb/e2008-00386-3

2022 Impact factor 1.6

Condensed Matter and Complex Systems

Eur. Phys. J. B 66, 25-28 (2008)
https://doi.org/10.1140/epjb/e2008-00386-3

Temperature and magnetic field dependence of the voltage in GaAs films with superconducting Ga grains

B. L. Willems¹^a, D. M.J. Taylor¹, J. Fritzsche¹, M. Malfait¹, J. Vanacken¹, V. V. Moshchalkov¹, E. Montoya² and G. Van Tendeloo²

¹ INPAC-Institute for Nanoscale Physics and Chemistry, Nanoscale Superconductivity and Magnetism Pulsed Fields Group, Katholieke Universiteit Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
² EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium

Corresponding author: ^a Bram.Willems@fys.kuleuven.be

Received: 23 November 2007
Revised: 12 September 2008
Published online: 11 October 2008

Abstract

We have studied granular films consisting of nanoscale Ga droplets formed on GaAs films via a method of vacuum annealing to promote As evaporation. For temperatures and magnetic fields below the bulk Ga critical parameters, the samples are very sensitive towards external microwave radiation when two point voltage measurements are performed. Together with the observation of an oscillating magnetic field dependence of the voltage, a scenario in which the samples consist of Josephson-coupled loops seems to be the most likely one for explaining the obtained results.

PACS: 74.78.-w – Superconducting films and low-dimensional structures / 74.81.Bd – Granular, melt-textured, amorphous, and composite superconductors

© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008