Related papers: Vortex lattice dynamics in a-NbGe detected by mode…
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…
The flux lattice driven by a uniform driving force in a superconductor with hot, strong, sharp and randomly distributed pinning centers, with applied magnetic field half the matching field is simulated. At low temperature both a non…
Triangular arrays of Ni nanotriangles embedded in superconducting Nb films exhibit unexpected dynamical vortex effects. Collective pinning with a vortex lattice configuration different from the expected fundamental triangular "Abrikosov…
We study the energetics of superconducting vortices in the SO(5) model for high-$T_c$ materials proposed by Zhang. We show that for a wide range of parameters normally corresponding to type II superconductivity, the free energy per unit…
We study the interplay between a novel vortex-loop unbinding in finite magnetic field at T=T_V and flux-line lattice (FLL) melting at T=T_M in type-II superconductors. The FLL melts due to nucleation of vortex loops parallel to c-axis,…
Nanowires of two-dimensional (2D) crystals of type-II superconductor NbSe$_2$ prepared by electron-beam lithography were studied, focusing on the effect of the motion of Abrikosov vortices. We present magnetoresistance measurements on these…
Investigations into the heterogeneous pinning properties of the vortex state created by partially nano-patterning single crystals of 2H-NbSe2 reveal an atypical magnetization response which is significantly drive dependent. Analysis of the…
We measure current-voltage characteristics as function of magnetic field and temperature in Nb strips of different thickness and width. The instability voltage of the flux flow state related to the vortex critical velocity v* is studied and…
The ratchet effect is demonstrated theoretically for the simple model of a vortex in a thin superconducting film interacting with a periodic array of magnetic dipoles placed in the vicinity of the film . The pinning potential for the vortex…
By means of the variational approximation (VA) and systematic simulations, we study dynamics and stability boundaries for solitons in a two-dimensional (2D) self-attracting Bose-Einstein condensate (BEC), trapped in an optical lattice (OL)…
The structure function of the vortex lattice of layered superconductor is calculated to one-loop order. Based on a phenomenological melting criterion concerning the Debye-Waller factor, we calculate the melting line of the vortex lattice,…
The superfluid density is calculated theoretically for incompressible vortex lattices in two dimensions that have isolated dislocations quenched in by a random arrangement of pinned vortices. The latter are assumed to be sparse and to be…
The four-roll mill has been traditionally viewed as a device generating simple extensional flow with a central stagnation point. Our systematic investigation using a two-relaxation-time regularized lattice Boltzmann (TRT-RLB) model reveals…
The finite temperature dynamical phases of vortices in films driven by a uniform force and interacting with the periodic pinning potential of a square lattice of columnar defects are investigated by Langevin dynamics simulations of a London…
The vortex dynamics in a low temperature superconductor deposited on top of a rectangular array of micrometer size permalloy triangles is investigated experimentally. The rectangular unit cell is such that neighboring triangles physically…
A vortex-induced transverse voltage in a superconducting film, previously predicted theoretically, has been seen experimentally for the first time. The magnitude of this voltage and its nonmonotonic current dependence are explained on the…
We explore in detail the angular dependent vortex dynamics in type II superconductors with aligned columnar defects introduced by irradiation with very energetic heavy-ions. We use dc magnetization measurements deep in the vortex solid…
To investigate the dynamics of driven vortices in superconductors, noise in the local vortex density was investigated in the mixed state of a high-$T_c$ superconductor, Bi$_2$Sr$_2$CaCu$_2$O$_y$, using a two-dimensional electron gas (2DEG)…
The full H-T phase diagram in the nematic superconductor FeSe is mapped out using specific-heat and thermal-expansion measurements down to 0.7 K and up to 30 T for both field directions. A clear thermodynamic signal of an underlying…
We consider a superconducting film, placed upon a magnetic dot array. Magnetic moments of the dots are normal to the film and randomly oriented. We determine how the concentration of the vortices in the film depends on the magnetic moment…