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Using the nonlinear Ginzburg–Landau equations we study the vortex configurations in a superconducting square with a central square pillar in the presence of a uniform applied magnetic field. The presence of the pillar changes the vortex structure in the superconducting sample considerably. We calculate magnetization, magnetic induction, supercurrent and vorticity, which show different vortex configurations as a function of magnetic field. [ABSTRACT FROM AUTHOR]

The resistive state of a superconductor in magnetic field has been thoroughly investigated both by experiments and by theoretical simulations. However, a local study of vortex dynamics inducing dissipation was performed only recently by means of scanning Hall probe microscopy (SHPM). In this work we extend this idea and we visualize the oscillatory motion of vortices in NbSe2 using scanning tunneling microscopy (STM). In contrast to previous experiments, sensitive to magnetic fields, the STM probes the local density of states and the local topography. Its ability to resolve vortices is limited by the coherence length. In the case of type-II superconductors this is expected to resolve vortex motion beyond the detection limit of the SHPM. We experimentally verify the enhanced sensitivity by observing vortex motion in a very dense vortex lattice (H=600mT). [ABSTRACT FROM AUTHOR]

In this work we solved the time-dependent Ginzburg-Landau equations, TDGL, to simulate two superconducting systems with different lateral sizes and with an antidot inserted in the center. Then, by cycling the external magnetic field, the creation and annihilation dynamics of a vortex-antivortex pair was studied as well as the range of temperatures for which such processes could occur. We verified that in the annihilation process both vortex and antivortex acquire an elongated format while an accelerated motion takes place. [ABSTRACT FROM AUTHOR]

In order to study site-selective NMR in chiral p -wave superconductors, we calculate local nuclear relaxation rate T 1 − 1 in the vortex lattice state by Eilenberger theory with and without non-magnetic impurity scattering in the Born limit and unitary limit. The local T 1 − 1 in the NMR resonance line shape is different between two chiral states p ± , depending on whether the chirality is parallel or anti-parallel to the vorticity. In the p − -wave, anomalous suppression of local T 1 − 1 occurs around the vortex core due to the negative coherence term coming from odd-frequency s -wave Cooper pair induced around the vortex. We especially examine the site dependence of the anomalous suppression of local T 1 − 1 , including the applied magnetic field dependence and the impurity effects. [ABSTRACT FROM AUTHOR]