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Joule heat generated by resistive elements of cryogenic micro- and nanodevices often originates boiling of the cooling cryogenic liquids (helium, nitrogen). The article proposes an experimental method to explore the dynamics of the formation and development of a single vapor bubble in cryogenic liquid by sensing the temperature change of a superconducting thin-film microbridge being in the resistive state with single phase slip center or line. It serves both the source of heat for generating single bubbles and the surface temperature sensor due to its temperature-dependent excess current. The average bubble detachment rate and the average single bubble volume were experimentally determined for nucleate helium boiling. The obtained values are in good agreement with the data of other authors found in literature. [ABSTRACT FROM AUTHOR]

Studies of the Abrikosov vortex motion in superconductors based on time-dependent Ginzburg–Landau equations reveal an opportunity to detect the values of the Aharonov–Bohm type curl-less vector potentials without closed-loop electron trajectories encompassing the magnetic flux. [ABSTRACT FROM AUTHOR]

We have studied the destruction of the superconductivity in narrow YBCO strips at different temperatures caused by an electrical current pulse. Different dissipative regimes can be distinguished, and phase slip center (PSC) are more likely to appear for an overcritical current and close to the transition temperature T . However, far below T , the dissipation generates a hotspot (HS). Temperatures reached in these modes were calculated based on the Joule effect. The results of these computations are consistent with all the specific cases, PSCs and HSs, measured experimentally. One of the most attractive applications of the superconductivity at non-equilibrium regime is the single photon detection. Its principle relies on the hotspot phenomena and mainly the heat evacuation, which can determine the reset time of the photon detection. [ABSTRACT FROM AUTHOR]

Abstract: Voltage–current (V(I)) characteristics are investigated in the superconducting state of an equilateral triangle of 2.2μm2 area. Several steps in the V(I) curves indicate the presence of phase slip centers in the triangle. The field dependence of these steps follows the Little-Parks oscillations of the phase boundary, associated with the change of vorticity. The influence of the contacts manifests itself as an excess voltage and a negative differential resistance. In addition we show that the position of the current contacts modify the superconducting phase boundary measurements. [Copyright &y& Elsevier]

Abstract: The problem of phase slip centers in superconducting wires with forced current is studied. It is shown that when the wire is uniform and the temperature and current are in a certain regime in the parameter plane, phase slip centers appear periodically in time at the center of the wire. When the wire is not uniform, the phase slip centers are not stationary, but rather they move through convection by the thickness variation. [Copyright &y& Elsevier]

We demonstrate long-range superconducting correlations in a several-micrometers-long carbon nanotube bundle encapsulated in a van der Waals stack between hBN and NbSe 2 . We show that a substantial supercurrent flows through the nanotube section beneath the NbSe 2 crystal as well as through the 2 μm long section not in contact with it. The large in-plane critical magnetic field of this supercurrent is an indication that even inside the carbon nanotube Cooper pairs enjoy a degree of paramagnetic protection typical of the parent Ising superconductor. As expected for superconductors of nanoscopic cross section, the current-induced breakdown of superconductivity is characterized by resistance steps due to the nucleation of phase slip centers. All elements of our hybrid device are active building blocks of several recently proposed setups for realization of Majorana fermions in carbon nanotubes.