Related papers: Dendritic magnetic instability in superconducting …
We report magnetoresistance measurements through Nb films having a periodic thickness modulation. The cylinder shaped large-thickness regions of the sample, which form a square lattice, act as repulsive centers for the superconducting…
Current-voltage (I-V) characteristics of quench condensed, superconducting, ultrathin $Bi$ films in a magnetic field are reported. These I-V's show hysteresis for all films, grown both with and without thin $Ge$ underlayers. Films on Ge…
Magneto-optical imaging is used to visualize vortex avalanches in MgB2 films at 4K. Avalanches ranging from 50 to 50000 vortices were detected. The size distribution function has a clear peak whose position moves towards larger sizes as the…
Magnetic-dipolar-mode (MDM) oscillations in a quasi-2D ferrite disk show unique dynamical symmetry properties resulting in appearance of topologically distinct structures. Based on the magnetostatic (MS) spectral problem solutions, in this…
We report resistivity and magnetization of single crystal MgB2, focusing on the broadening of superconducting (SC) transition in magnetic fields. In-plane and out-of-plane resistivity indicate that the broadening of superconducting…
A perpendicular magnetic field penetrating a thin type-II superconductor slab produces vortices, with one vortex per flux quantum, h/2e. The vortices interact repulsively and form an ordered array (Abrikosov lattice) in clean systems, while…
The competition between intrinsic disorder in superconducting YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ (YBCO) thin films and an ultradense triangular lattice of cylindrical pinning centers spaced at 30 nm intervals results in an ordered Bose glass…
We study the influence of thermal fluctuations on the magnetic behavior of square mesoscopic superconductors. The strength of thermal fluctuations are parameterized using the Ginzburg number, which is small ($G_i \approx 10^{-10}$) in…
The conditions for the entry of vortices into type-II superconductors being in the Meissner and/or mixed state, are studied by both numerical and analytical solution of the Ginzburg-Landau equations. A modulation instability of the…
The work reported in my doctoral thesis is an experimental study of vortex dynamics and phase transitions in thin films of type II superconductors using scanning tunneling spectroscopy, low frequency ac susceptibility measurements and…
We report a comprehensive study of the complex AC conductivity of thin effectively 2D amorphous superconducting InO_x films at zero applied field. Below a temperature scale T_c0 where the superconducting order parameter amplitude becomes…
Highly dense MgB2 policrystalline bulk materials, obtained by reactive liquid infiltration, have been characterized in their superconducting transport and magnetic properties in magnetic field and in a temperature range of interest for the…
Using a Ginzburg-Landau model, we study the vortex behavior of a rectangular thin film superconductor subjected to an applied current fed into a portion of the sides and an applied magnetic field directed orthogonal to the film. Through a…
The review considers bulk MgB2-based materials in terms of their structure, superconducting and mechanical properties. Superconducting transition temperatures of 34.5-39.4 K, critical current densities of 1.8-1.0 x E6 A/sq.cm in self field…
The topological nature of magnetic-vortex state gives rise to peculiar magnetization reversal observed in magnetic microdisks. Interestingly, magnetostatic and exchange energies which drive this reversal can be effectively controlled in…
Magnetic transition metal dichalcogenide (TMD) films have recently emerged as promising candidates to host novel magnetic phases relevant to next-generation spintronic devices. However, systematic control of the magnetization orientation,…
We present numerical and analytical studies of coupled nonlinear Maxwell and thermal diffusion equations which describe nonisothermal dendritic flux penetration in superconducting films. We show that spontaneous branching of propagating…
Magneto-optical imaging was used to observe dendritic flux avalanches connecting the outer and inner edges of a ring-shaped superconducting MgB2 film. Such avalanches create heated channels across the entire width of the ring, and inject…
The structural, magnetic, and magnetocaloric properties of epitaxial Ni-Co-Mn-Al thin films with different compositions have been studied. The films were deposited on MgO(001) substrates by co-sputtering on heated substrates. All films show…
We consider a superconducting film with Magnetic Dots Array (MDA) placed on it. Magnetic moments of these dots are supposed to be normal to the film and strong enough to create vortices in the superconducting film. Magnetic interaction…