Related papers: Cooper pair insulator in amorphous films induced b…
We first review evidence for the Cooper pair insulator (CPI) phase in amorphous nanohoneycomb (NHC) films. We then extend our analysis of superconducting islands induced by film thickness variations in NHC films to examine the evolution of…
A Cooper pair insulator (CPI) phase emerges near the superconductor-insulator transitions of a number of strongly-disordered thin film systems. Much recent study has focused on a mechanism driving the underlying Cooper pair localization. We…
Measurements of transport properties of amorphous insulating indium oxide thin films have been interpreted as evidence of the presence of superconducting islands on the insulating side of a disorder-tuned superconductor-insulator…
Ultrathin amorphous Bi films, patterned with a nano-honeycomb array of holes, can exhibit an insulating phase with transport dominated by the incoherent motion of Cooper pairs of electrons between localized states. Here we show that the…
The microscopic nature of an insulating state in the vicinity of a superconducting state, in the presence of disorder, is a hotly debated question. While the simplest scenario proposes that Coulomb interactions destroy the Cooper pairs at…
We have studied the insulator-superconductor transition (IST) by tuning the thickness in quench-condensed $Bi$ films. The resistive transitions of the superconducting films are smooth and can be considered to represent "homogeneous" films.…
We present investigations of the superconductor to insulator transition (SIT) of uniform a-Bi films using a technique sensitive to Cooper pair phase coherence. The films are perforated with a nanohoneycomb array of holes to form a multiply…
We have studied the magnetic field or disorder induced insulating and metallic phases in amorphous Ta superconducting thin films. The evolution of the nonlinear transport in the insulating phase exhibits a non-monotonic behavior as the…
Recent studies suggests that in disordered ultrathin films superconducting (SC) state may be intrinsically inhomogeneous. Here we investigate the nature of SC state in ultrathin Nb films, of thickness $d$ ranging from 1.2 nm to 20 nm, which…
Experiments show that the Cooper pair transport in the insulator phase that forms at thin film superconductor to insulator transitions (SIT) is simply activated. This activated behavior depends on the microscopic factors that drive the…
Nonlinear I-V characteristics have been observed in insulating quench-condensed films which are locally superconducting. We suggest an interpretation in terms of the enhancement of conduction by the depinning of a Cooper pair charge density…
Two experiments are described which are related to the problem of localized Cooper pairs. Magnetic-field-tuned superconductor-insulator transition was studied in amorphous In--O films with onset of the superconducting transition in zero…
A picture of pair scattering on Wigner crystal islands for the earlier proposed superconducting state in BCS superconductor with characteristic HTSC properties is presented. The model is supposed to be valid for thin heterogeneous films and…
Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band…
Properties of disordered thin films are discussed based on the viewpoint that superconducting islands are formed in the system. These lead to superconducting correlations confined in space, which are known to form spontaneously in thin…
Recent scanning tunnelling microscopy experiments in NbN thin disordered superconducting films found an emergent inhomogeneity at the scale of tens of nanometers. This inhomogeneity is mirrored by an apparent dimensional crossover in the…
We conducted a systematic study of the disorder dependence of the termination of superconductivity, at high magnetic fields (B), of amorphous indium oxide films. Our lower disorder films show conventional behavior where superconductivity is…
Rapid miniaturization of electronic devices and circuits demands profound understanding of fluctuation phenomena at the nanoscale. Superconducting nanowires -- serving as important building blocks for such devices -- may seriously suffer…
We study a Cooper-pair transistor realized by two Josephson weak links that enclose a superconducting island in an InSb-Al hybrid nanowire. When the nanowire is subject to a magnetic field, isolated subgap levels arise in the…
Spatially extended aggregates of dopants are ubiquitous in a plethora of granular superconductors, forming a droplet network that is very important to their characterization and to the description of their superconducting properties. At the…