Related papers: Two-stage dissipation in a superconducting microbr…
The universal behaviour of superconductors near the phase transition is described by the three-dimensional field theory of scalar quantum electrodynamics. We approximately solve the model with the help of non-perturbative flow equations. A…
Bulk superconductor samples of YBa2Cu3-xCoxO7-{\delta} with x = 0, 0.01, 0.03, 0.05 are synthesized by solid-state reaction route. Both x-ray diffraction and electron microscopy have been employed to study the phase identification,…
Heat transport in the cuprate superconductors YBa$_2$Cu$_3$O$_{y}$ and La$_{2-x}$Sr$_x$CuO$_4$ was measured at low temperatures as a function of doping. A residual linear term kappa_{0}/T is observed throughout the superconducting region…
The nature of the pseudogap phase of cuprate high-temperature superconductors is a major unsolved problem in condensed matter physics. We studied the commencement of the pseudogap state at temperature T* using three different techniques…
Current-voltage curves of small area hysteretic intrinsic Josephson junctions, for which the Josephson energy $E_J=\hbar J_c/2e$ is of order of thermal energy $kT$, are investigated. A non-monotonic temperature dependence of the switching…
We present low-temperature scanning electron microscopy (LTSEM) investigations of superconducting microbridges made from ultrathin NbN films as used for hot electron bolometers. LTSEM probes the thermal structure within the microbridges…
Superconducting vortices and phase slips are primary mechanisms of dissipation in superconducting, superfluid, and cold atom systems. While the dynamics of vortices is fairly well described, phase slips occurring in quasi-one dimensional…
We show that a clean multiband superconductor may display one or several phase transitions with increasing temperature from or to frustrated configurations of the relative phases of the superconducting order parameters. These transitions…
We discuss the occurrence of crossing points in the magnetization - temperature $(m,T$) plane within the framework of critical phenomena. It is shown that in a two-dimensional superconducting slab of thickness $d_{s}$ $m_{z}(\delta)$ versus…
Phase-coherent diffusive transport through mesoscopic hybrid superconductor/normal metal tunneling structures is investigated. For a N-s-S two-barrier tunneling system with bulk S and N electrodes coupled by a mesoscopic superconducting…
The recently proposed theoretical model of superconductors endowed with two distinct superconducting phases and critical temperatures is further analyzed by introducing two distinct order parameters, described by two scalar fields which…
By use of the multi-Josephson junction model, we investigate voltage-biased I-V characteristics. Differently from the case of the single junction, I-V characteristics show a complicated behavior due to inter-layer couplings among…
In classical superconductors an energy gap and phase coherence appear simultaneously with pairing at the transition to the superconducting state. In high-temperature superconductors, the possibility that pairing and phase coherence are…
A superconducting transition in the temperature dependence of the ab-plane resistivity of underdoped YBa_2Cu_3O_{6+x} crystals in the range T_c<30 K has been investigated. Unlike the case of samples with the optimal level of doping, the…
We study numerically the temperature dependencies of specific heat, susceptibility, penetration depth, and thermal conductivity of a coupled $(d_{x^2-y^2}+is)$-wave Bardeen-Cooper-Schreiffer superconductor in the presence of a weak s-wave…
Superconductors exhibit dissipationless supercurrents even under finite bias and magnetic field conditions, provided these remain below the critical values. However, type-II superconductors in the flux flow regime display Ohmic dissipation…
Amorphous solids show surprisingly universal behaviour at low temperatures. The prevailing wisdom is that this can be explained by the existence of two-state defects within the material. The so-called standard tunneling model has become the…
Motivated by experiments with current biased superconducting atomic point contacts the general problem of nonadiabatic transitions between adiabatic surfaces in presence of strong dissipation is studied. For a single channel device the…
Vanadium dioxide (VO2) exhibits a hysteretic insulator-to-metal transition near room temperature, forming the foundation for various forms of resistive switching devices. Usually, these are realized in the form of two-terminal bridge-like…
The single-particle density of states and the tunneling conductance are studied for a two-dimensional BCS-like Hamiltonian with a d_{x^2-y^2}-gap and phase fluctuations. The latter are treated by a classical Monte Carlo simulation of an XY…