Related papers: Absence of a Zero Temperature Vortex Solid Phase i…
Superconductors have two key characteristics. They expel magnetic field and they conduct electrical current with zero resistance. However, both properties are compromised in high magnetic fields which can penetrate the material and create a…
We investigate transition to the superconducting state in the ultrathin titanium nitride films on approach to superconductor-insulator transition. Building on the complete account of quantum contributions to conductivity, we demonstrate…
In Type II superconductors, the vortex lattice can exhibit "inverse melting," transitioning from a liquid to a crystalline solid as temperature increases. While recently observed via scanning tunneling microscopy in a 20 nm thick amorphous…
A surprisingly strong variation of resistance with perpendicular magnetic field, and a peak in the resistance vs. field, R(B) has been found in insulating films of a sequence of homogeneous, quench-condensed films of amorphous Bi undergoing…
We investigate the phenomenon of decay of a supercurrent in a superconducting thin film in the absence of an applied magnetic field. The resulting zero-temperature resistance derives from two equally possible mechanisms: 1) quantum…
We have studied the magnetic-field-tuned superconductivity destroying quantum transition in amorphous In-O films with the onset of superconductivity in zero field at about 2 K. At temperatures down to 30 mK the critical resistance…
We have studied the superconducting behavior of 100 nm Titanium Nitride (TiN) thin film in a perpendicular magnetic field. We found a zero field transition temperature of 4.6 K and a slope in the H-T plane of -0.745 T/K. At 4.2 K, we have…
Strongly disordered superconductors in a magnetic field display many characteristic properties of type-II superconductivity--- except at low temperatures where an anomalous linear $T$-dependence of the resistive critical field $B_{c2}$ is…
We have studied mixed-state dissipation in epitaxial MgB$_2$ thin films by measurements of resistive transition, current-voltage characteristics, Hall effect, and point-contact tunnelling spectrum. We found that unlike single gap…
Magnetic field and electrostatically tuned superconductor-insulator (SI) transitions of ultrathin metal films with levels of disorder that place them near the disorder-tuned SI transition appear to be direct, continuous quantum phase…
We study the low temperature magnetoresistance of dirty thin films and quantum wires close to a quantum phase transition from a superconducting to normal state, induced by applying a parallel magnetic field. We find that the different…
Motivated by a recent controversy on a possible quantum phase in thin films of relatively clean superconductors under an out-of-plane magnetic field, the quantum fluctuation effects on the phase diagram and the resistivity are reexamined.…
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…
We investigate the field tuned quantum phase transition in a 2D low-disorder amorphous InO$_x$ film in the frequency range of 0.05 to 16 GHz employing microwave spectroscopy. In the zero temperature limit, the AC data are consistent with a…
We consider the problem of finite resistance $R$ in superconducting films with geometry of a strip of width $W$ near zero temperature. The resistance is generated by vortex configurations of the phase field. In the first type of process,…
Superconducting transition, defined as vanishing of the resistivity, under a magnetic field in a clean bulk type II superconductor with weak sample disorder is believed to be a reflection of freezing of the vortex liquid to a kind of vortex…
We report the experimental observation of a magnetic-field-tuned superconductor-insulator transition (SIT) in ultrathin TiN films. The low temperature transport properties of these films show scaling behavior consistent with a transition…
The interplay between superconductivity and magnetism gives rise to many intriguing and exciting phenomena. In this Letter we report about a novel manifestation of this interplay: a temperature induced phase transition between different…
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…
We investigate low-temperature transport properties of thin TiN superconducting films in the vicinity of the disorder-driven superconductor-insulator transition. In a zero magnetic field, we find an extremely sharp separation between…