Related papers: On the Abrikosov transition in disordered supercon…
We study the effects of an external magnetic field on thensuperconducting phase diagram of a quasi-two-dimensional system of Dirac electrons at an arbitrary temperature. At zero temperature, there is a quantum phase transition connecting a…
This report examines the thickness dependence of the reorientation phase transition in ferromagnetic films with perpendicular anisotropy. That is, we find the exact boundary of metastability of uniformly magnetized in-plane states as the…
Domain walls in magnetic multilayered systems can exhibit a very complex and fascinating behavior. For example, the magnetization of thin films of hard magnetic materials is in general perpendicular to the thin-film plane, thanks to the…
We investigate the temperature-disorder (T-S) phase diagram of a three-dimensional gauge glass model, which is a cubic-lattice nearest-neighbor XY model with quenched random phase shifts A_xy at the bonds, by numerical Monte Carlo…
All higher-spin s >= 1/2 Ising spin glasses are studied by renormalization-group theory in spatial dimension d=3. The s-sequence of global phase diagrams, the chaos Lyapunov exponent, and the spin-glass runaway exponent are calculated. It…
As a part of my doctoral thesis, I studied the effect of phase fluctuations in two dimensional (2D) and three dimensional (3D) superconducting films of conventional s-wave superconductor, NbN, by measuring the electrodynamics response…
We study the effect in geometrically frustrated antiferromagnets of weak, random variations in the strength of exchange interactions. Without disorder the simplest classical models for these systems have macroscopically degenerate ground…
We present results on disordered amorphous films which are expected to undergo a field-tuned Superconductor-Insulator Transition. Based on low-field data and I-V characteristics, we find evidence of a low temperature Metal-to-Superconductor…
We study the three-dimensional system of magnetic nanoparticle dipoles randomly oriented along quenched easy axes. Directions of the magnetic momenta are described by the Ising variables which allow the momenta to flip along their random…
The origin of the intermediate anomalous metallic state in two-dimensional superconductor materials remains enigmatic. In the present paper, we observe such a state in a series of $\sim$9.0 nm thick Ta$_x$(SiO$_2$)$_{1-x}$ ($x$ being the…
A systematic treatment of the magnetic fluctuations effect on the properties of the normal-to-superconducting phase transition in a zero external magnetic field is given within the self-consistent approximation and the quasi-macroscopic…
Superconducting transport properties of granular materials are greatly influenced by the microstructure. We show that in heavily boron-doped diamond films (HBDDF) films some sharp transport features can be manipulated by applying a magnetic…
The interplay between disorder and interactions can dramatically influence the physical properties of thin-film superconductors. In the most extreme case, strong disorder is able to suppress superconductivity as an insulating phase emerges.…
It is well known that external magnetic fields and magnetic moments of impurities both suppress superconductivity. Here, we demonstrate that their combined effect enhances the superconductivity of a few atomic layer thick Pb films grown on…
In the first part of this work an overview of the available data on the paramagnetic effect recently discovered in superconductors was given as well as a possible explanation of the effect. Here the consequences caused by this weakly…
A study of magnetic-field tuned superconductor-insulator transitions in amorphous $Nb_{0.15}Si_{0.85}$ thin films shows that quantum superconductor-insulator transitions are characterized by an unambiguous signature -- a kink in the…
We present the phase diagram for the current states of superconducting films, based on the experimental investigation of the resistive transition induced by transport current. We found that a rather narrow film never enters the vortex…
The scaling properties of the free energy, the diamagnetic moment, and the diamagnetic susceptibility above the phase transition from the ferromagnetic phase to the phase of coexistence of ferromagnetic order and superconductivity in…
A recent letter [Lin & Goldman, Phys. Rev. Lett. 106, 127003 (2011)] has presented experimental data in highly disordered thin films, which were interpreted as a quantum phase transition, an intriguing and surprising result for this system.…
We show that inhomogeneities in the spatial distribution of Cooper pairs and in the phase of the local superconducting order parameter in the vicinity of a superconductor-normal state transition (SNT) in two dimensions can be highly…