Related papers: V-I characteristics in the vicinity of order-disor…
Recent studies have shown a number of surprising vortex dynamics phenomena both in low and high temperature superconductors, which include: low frequency noise, slow voltage oscillations, history dependent dynamic response, memory of the…
In single crystals of 2H-NbSe2, we identify for the first time a crossover from weak collective to strong pinning regime in the vortex state which is not associated with the peak effect phenomenon. Instead, we find the crossover is…
The magnetic field $B$ dependence of the critical current $I_c$ for the vortex phase of a disordered superconductor is studied numerically at zero temperature. The $I_{c}(B)$ increases rapidly near the upper critical field $B_{c2}$ similar…
We report self-consistent quasiclassical calculations of spontaneous currents and magnetic moments in finite size unconventional superconducting systems, namely: (i) in isolated d-wave superconductor islands where, in addition to the…
In a type-II superconductor the generation of higher harmonics in the magnetic response to an alternating magnetic field is a consequence of the non-linearity in the I-V relationship. The shape of the current-voltage (I-V) curve is…
It is commonly accepted that the peak effect (PE) in the critical current density of type II superconductors is a consequence of an order-disorder transition in the vortex lattice (VL). Examination of vortex lattice configurations (VLCs) in…
Order-disorder transitions take place in many physical systems, but observing them in detail in real materials is difficult. In two- or quasi-two-dimensional systems, the transition has been studied by computer simulations and…
The work presented in my doctoral thesis is an experimental investigation of the nature of order to disorder transition of vortex lattice in a Type-II superconductor namely Co-intercalated 2H-NbSe2 using scanning tunnelling spectroscopy and…
A field theoretical method is developed which permits us to study the dynamics of vortices in disordered environments. In particular, we obtain a self-consistent system of equations for disorder averaged quantities. Making use of a…
A dc voltage drop develops along amorphous indium oxide nanowires that are exposed to an ac bias source. This voltage is anti-symmetric with magnetic field and is characterized by sample specific quasi-periodic magneto-voltage oscillations.…
We report structural evidence of dynamic reorganization in vortex matter in clean NbSe$_2$ by joint small angle neutron scattering and ac-susceptibility measurements. The application of oscillatory forces in a transitional region near the…
Dynamic ordering of driven vortex matter has been investigated in the peak effect regime of both amorphous MoGe films and 2H-NbSe2 crystals by mode locking (ML) and dc transport measurements. ML features allow us to trace how the shear…
Using numerical simulations of magnetically interacting vortices in disordered layered superconductors we obtain the static vortex phase diagram as a function of magnetic field and temperature. For increasing field or temperature, we find a…
We examine metastable and transient effects both above and below the first-order disorder driven decoupling line in a 3D simulation of magnetically interacting pancake vortices. We observe pronounced transient and history effects as well as…
Vortices in type-II superconductors driven over random disorder are known to exhibit a remarkable variety of distinct nonequilibrium dynamical phases that arise due to the competition between vortex-vortex interactions, the quenched…
The peak effect in weakly pinned superconductors is accompanied by metastable vortex states. Each metastable vortex configuration is characterized by a different critical current density J_c, which mainly depends on the past thermomagnetic…
We study the zero-temperature dynamic transition from the disordered flow to an ordered flow state in driven vortices in type-II superconductors. The transition current $I_{p}$ is marked by a sharp kink in the $V(I)$ characteristic with a…
In magnetic superconductors a moving vortex lattice is accompanied by an ac magnetic field which leads to the generation of spin waves. At resonance conditions the dynamics of vortices in magnetic superconductors changes drastically,…
We examine the statics and dynamics of vortices in the presence of a periodic quasi-one dimensional substrate, focusing on the limit where the vortex lattice constant is smaller than the substrate lattice period. As a function of the…
Vortex matter in layered high-$T_c$ superconductors, including iron-pnictides, undergo several thermodynamic phase transitions due to the complex interplay of pinning energy, thermal energy and elastic energy. Moreover, the presence of…