B. Rosenstein

First-principles theory of fluctuations in vortex liquids and solids

Consistent perturbation theory for thermodynamical quantities in type II superconductors in magnetic field at low temperatures is developed. It is complementary to the existing expansion valid at high temperatures. Magnetization and specific heat are calculated to two loop order and compare well to existing Monte Carlo simulations and experiments.

Quantum regime of Cooper pair tunneling in small-area Bi2Sr2CaCu2O8+δ mesas in magnetic fields

Abstract We show that application of an c-axis magnetic field decreases the effective interlayer Josephson coupling in small-area Bi2Sr2CaCu2O8+δ (Bi-2212) mesas at low temperatures. As magnetic field increases, the crossover from the classical regime of Cooper pair tunneling to the quantum regime leads to an additional drastic suppression of the Josephson coupling due to the Coulomb blockade. As result, the stack of many intrinsic junctions is nonsuperconducting at high fields. The quantum regime of superconducting tunneling may be reached in mesas with N junctions and area 0.3 μm 2 made of intercalated Bi-2212 crystals by applying c-axis magnetic fields B>4/N2 T at N≫1.

Coreless vortex in p-wave superconductor

Abstract We have considered coreless vortices in p-wave superconductors for arbitrary ratio κ=λ/ξ (here λ and ξ are the magnetic length and the coherence length correspondently). Both order parameter and magnetic field of the coreless vortex decaying from the vortex axis demonstrate essential difference of the vortex structure for different κ parameter and from those calculated for the vortex in liquid He3. In particular, strong asymmetry usual for some of the components of the order parameter disappears when κ parameter approaches 1.

Shock Waves and Avalanches in Type‐II Superconductors

Rapid penetration of magnetic flux into a Meissner phase of the type‐II superconductor is studied analytically and numerically. A sharp shock wave front of the magnetic induction is formed due to the non‐analyticity of the resistivity at the transition from the mixed to the normal state. The shock wave magnetic induction and the temperature profiles move with constant velocity determined by the Joule heat produced by the electric current in the normal domain at the flux front. If the normal state resistance of the sample material is temperature dependent (like in HTSC), then the straight front shows instability. For a sufficiently small thermal diffusion constant a finger shaped avalanches are formed.