Quantum fluctuations in percolating superconductors: an evolution with effective dimensionality.
We investigate percolating films of superconducting nanoparticles and observe an evolution from superconducting to metallic to insulating states as the surface coverage of the nanoparticles is decreased. We demonstrate that this evolution is correlated with a reduction in the effective/dominant dimensionality of the system, from 2D to 1D to 0D, and that the physics in each regime is dominated by vortices, phase slips and tunnelling respectively. Finally we construct phase diagrams that map the various observed states as a function of surface coverage (or, equivalently, normal state resistance), temperature and measurement current.
The MacDiarmid Institute for Advanced Materials and Nanotechnology, Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
Amol
A
Nande
Shawn
S
Fostner
Jack
J
Grigg
Alex
A
Smith
Kristiaan
K
Temst
Margriet J Van
MJ
Bael
Simon A
SA
Brown