Related papers: Unexpectedly wide reversible vortex region in $\be…
We have studied the vortex dynamics in the PrFeAsO$_{0.60}$F$_{0.12}$ superconducting sample by dc magnetization and dynamic magnetization-relaxation rate $(Q)$ measurements. The field dependence of the superconducting irreversible…
We have measured the irreversible magnetization M_i of an ErBa_2Cu_3O_7 single crystal with columnar defects (CD), using a technique based on sample rotation under a fixed magnetic field H. This method is valid for samples whose…
Competition with magnetism is at the heart of high temperature superconductivity, most intensely felt near a vortex core. To investigate vortex magnetism we have developed a spatially resolved probe using nuclear magnetic resonance. Our…
The superconducting transition of the ?-pyrochlore oxide KOs2O6 with Tc = 9.60 K is studied by resistivity measurements under various magnetic fields using a high-quality single crystal. The reentrant behavior of superconductivity is…
We present reversible magnetization measurements on MgB2 single crystals in magnetic fields up to 2.5 T applied parallel to the crystal's c-axis. This magnetization is analyzed in terms of the Hao-Clem model, and various superconducting…
Rare-earth pyrochlores are known to exhibit exotic magnetic phenomena. We report a study of crystal growth and characterizations of a new rare-earth compound Er$_2$AlSbO$_7$, in which Al$^{3+}$ and Sb$^{5+}$ ions share the same positions…
This work is the sequel of a previous investigation of stationary and cylindrically symmetric vortex configurations for simple models representing an incompressible non-relativistic superconductor in a rigidly rotating background. In the…
Muon spin rotation spectroscopy has been used to measure the effective size of the vortex cores in optimally doped YBa2Cu3O6.95 as a function of temperature and magnetic field deep in the superconducting state. While the core size at H=2T…
We present magnetization studies as a function of time, temperature and magnetic field for $H$ $\parallel$ c-axis, in a hole-doped pnictide superconductor, La$_{0.34}$Na$_{0.66}$Fe$_2$As$_2$, with, $T_c$ $\approx$ 27 K. The obtained vortex…
We observe a hysteretic reorientation of the magnetic vortex lattice in the noncentrosymmetric superconductor Ru7B3, with the change in orientation driven by altering magnetic field below Tc. Normally a vortex lattice chooses either a…
Magneto-resistivity of a c-axis oriented MgB$_{2}$ thin film was studied in perpendicular and parallel magnetic fields up to $\sim $23 T with temperatures down to 0.38 K. Resistive critical magnetic fields were determined. Large separations…
We report on isofield magnetization curves obtained as a function of temperature in two single crystals of $Ba_{1-x}K_xFe_2As_2$ with superconducting transition temperature $T_c$=28K and 32.7 K. Results obtained for fields above 20 kOe show…
We present a magnetic phase diagram of rare-earth pyrochlore $\rm{Yb_2Ti_2O_7}$ in a $\langle 111 \rangle$ magnetic field. Using heat capacity, magnetization, and neutron scattering data, we show an unusual field-dependence of a first-order…
We have investigated the magnetic phase diagram of a fully oxygenated detwinned YBa2Cu3O7 single crystal by means of a combination of a low-temperature thermal analysis (DTA) technique with a simultaneous application of a small oscillating…
Some frustrated pyrochlore antiferromagnets, such as Y2Mo2O7, show a spin-freezing transition and magnetic irreversibilities below a temperature Tf similar to what is observed nonlinear magnetization measurements on Y2Mo2O7 that provide…
The magnetic field distribution in the vortex state of YNi2B2C has been probed by muon spin rotation (muSR). The analysis based on the London model with nonlocal corrections shows that the vortex lattice has changed from hexagonal to square…
The remarkable phenomenon of weak magnetization hysteresis loops, observed recently deep in the vortex-liquid state of a nearly two-dimensional (2D) superconductor at low temperatures, is shown to reflect the existence of an unusual…
We report the magnetic-field dependence of the irreversible magnetization of the recently discovered binary superconductor MgB$_{2}$. For the temperature region of $T< 0.9T_c$, the contribution of the bulk pinning to the magnetization…
We performed the first scanning tunneling spectroscopy measurements on the pyrochlore superconductor KOs2O6 (Tc = 9.6 K) in both zero magnetic field and the vortex state at several temperatures above 1.95 K. This material presents…
The interrelation between heterogeneity and flux pinning is studied in Ba(Fe1-xCox)2As2 single crystals with widely varying Co-content x. Magnetic Bitter decoration of the superconducting vortex ensemble in crystals with x = 0:075 and x =…