Related papers: The Superconductor-Insulator Transition in 2D
Superconducting thin-films are central to the operation of many kinds of quantum sensors and quantum computing devices: Kinetic Inductance Detectors (KIDs), Travelling-Wave Parametric Amplifiers (TWPAs), Qubits, and Spin-based Quantum…
All solid phases of bismuth under pressure, but one, have been experimentally found to superconduct. From Bi-I to Bi-V, avoiding Bi-IV, they become superconductors and perhaps Bi-IV may also become superconductive. To investigate the…
Measurements on resistivity and magnetic susceptibility have been carried out for Bi single crystals under pressures up to 10.5GPa. The temperature dependent resistivity shows a semimetallic behavior at ambient and low pressures (below…
Superconductivity has been found in RuN films obtained by reactive magnetron sputtering. This is a novel member of the metal nitride superconductors family. The critical temperature of the superconducting transition varies depending on the…
We use sub-Kelvin scanning tunneling spectroscopy to investigate the suppression of superconductivity in homogeneously disordered ultrathin MoC films. We observe that the superconducting state remains spatially homogeneous even on the films…
Transport data on Bi, MoGe, and PbBi/Ge homogeneously-disordered thin films demonstrate that the critical resistivity, $R_c$, at the nominal insulator-superconductor transition is linearly proportional to the normal sheet resistance, $R_N$.…
Motivated by the recent experimental observation of an intermediate bosonic metallic state in the two-dimensional superconductor-insulator transition at $T=0$, we study an extended Bose Hubbard model in the limit of large number of…
We have conducted a highly precise doping controlled experiment on a thin film of the single layer cuprate Bi2Sr2-xLaxCuOy (x = 0.6), in order to observe the superconducting insulating transition (SIT). Sr2+/La3+ substitution (x = 0.6)…
Measurements of resistance vs. temperature have been carried out on a sequence of quench-condensed ultrathin films of amorphous bismuth (a-Bi). The resistance below about 0.1K was found to be temperature independent in a range of films with…
We combine measurements of the longitudinal ($\rho_{xx}$) and Hall ($\rho_{xy}$) resistivities of disordered two dimensional amorphous indium-oxide films to study the magnetic-field tuned superconductor to insulator transition (H-SIT) in…
We study the zero-temperature phase transition of a two-dimensional disordered boson Hubbard model. The phase diagram of this model is constructed in terms of the disorder strength and the chemical potential. Via quantum Monte Carlo…
We investigate the insulating phase that forms in a titanium nitride film in a close vicinity of the disorder-driven superconductor-insulator transition. In zero magnetic field the temperature dependence of the resistance reveals a sequence…
The presented results are part of a feasibility study of superheated superconducting microstructure detectors. The microstructures (dots) were fabricated using thin film patterning techniques with diameters ranging from $50\mu$m up to…
Competing phenomena in low dimensional systems can generate exotic electronic phases, either through symmetry breaking or a non-trivial topology. In two-dimensional (2D) systems, the interplay between superfluidity, disorder and repulsive…
We study the superconductor to insulator transition at zero temperature in a Josephson-junction array model on a honeycomb lattice with $f$ flux quantum per plaquette. The path integral representation of the model corresponds to a…
We study theoretically orbital effects of a parallel magnetic field applied to a disordered superconducting film. We find that the field reduces the phase stiffness and leads to strong quantum phase fluctuations driving the system into an…
We analyse the finite-temperature phase diagram of a dipolar Bose Einstein Condensate confined in a tubular geometry. The effect of thermal fluctuations is accounted for by means of Bogoliubov theory employing the local density…
We review our recent measurements of the complex AC conductivity of thin InO_x films studied as a function of magnetic field through the nominal 2D superconductor-insulator transition. These measurements - the first of their type to probe…
We have patterned a hexagonal array of nano-scale holes into a series of ultrathin, superconducting Bi/Sb films with transition temperatures 2.65 K $<T_{co} < $5 K. These regular perforations give the films a phase-sensitive periodic…
Superconductor insulator transition in transverse magnetic field is studied in the highly disordered MoC film with the product of the Fermi momentum and the mean free path $k_F*l$ close to unity. Surprisingly, the Zeeman paramagnetic…