相关论文: Vortex phase transformations probed by the local a…
The angular dependence of the first-order phase transition (FOT) in the vortex lattice in Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8}$ crystals was investigated by a low frequency AC shielding technique (with the AC field $\parallel c$), in which the…
The vortex lattice melting transition in single crystals Bi2Sr2CaCu2O8+d was studied by the in-plane resistivity measurements in magnetic fields tilted away from the c-axis to the ab-plane. In order to avoid the surface barrier effect which…
Measurements of non-local in-plane resistance originating from transverse vortex-vortex correlations have been performed on a Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} high-T_c superconductor in a magnetic field up to 9 T applied along the crystal…
In this work we revisit the vortex matter phase diagram in layered superconductors solving still open questions by means of AC and DC local magnetic measurements in the paradigmatic Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8}$ compound. We show that…
Magnetization and ac-susceptibility measurements are used to characterize the mixed phase of the high-temperature cuprate superconductor La$_{2-x}$Sr$_{x}$CuO$_{4}$ over a large range of doping (0.075 $\leq x\leq$ 0.20). The first order…
The vortex liquid-to-glass transition has been studied in Ba0.72K0.28Fe2As2, Ba0.9Co0.1Fe2As2, and Ba(Fe0.45Ni0.05)2As2 single crystal with superconducting transition temperature, Tc = 31.7, 17.3, and 18 K, respectively, by…
Vortex matter phase transitions in the high-temperature superconductor Bi2Sr2CaCu2O8 were studied using local magnetization measurements combined with a vortex 'shaking' technique. The measurements revealed thermodynamic evidence of a…
Vortex phase diagram under tilted fields from the $c$ axis in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+y}$ is studied by local magnetization hysteresis measurements using Hall probes. When the field is applied at large angles from the $c$ axis, an…
Time-resolved local induction measurements near to the vortex lattice order-disorder transition in optimally doped Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ single crystals shows that the high-field, disordered phase can be quenched to…
Using high sensitivity magneto-optical imaging we find evidence for a jump in local vortex density associated with a vortex liquid to solid phase transition just above the lower critical field in a single crystal of Bi2Sr2CaCu2O8. We find…
We present a new probe for the first-order transition for layered vortex matter: A second step in the screening of an ac field that is independent of the frequency and amplitude of the excitation. This second step is observed in the…
Measurements of magnetotransport and current-voltage (I-V) characteristics up to 9 T were used to investigate the vortex phase diagram of an under-doped Measurements of magnetotransport and current-voltage (I-V) characteristics up to 9 T…
Using differential magneto-optical imaging, we address the question of mesoscopic inhomogeneity in underdoped Bi-2212 single crystals. Among other features, it is shown that an anomalous temperature dependence of the penetration field and…
The persistence of the first-order transition line in the phase diagram of mesoscopic Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8}$ vortex matter is detected down to a system size of less than hundred vortices. Precise and highly-sensitive to bulk…
The vortex correlation along the c-axis in high quality single crystals of YBa$_{2}$Cu$_{4}$O$_{8}$ has been investigated as a function of temperature T in different magnetic fields, using the quasi-flux transformer configuration. A…
The thermodynamic $H-T$ phase diagram of Bi$_2$Sr$_2$CaCu$_2$O$_8$ was mapped by measuring local \emph{equilibrium} magnetization $M(H,T)$ in presence of vortex `shaking'. Two equally sharp first-order magnetization steps are revealed in a…
The vortex dynamics of Bi$_2$Sr$_2$Ca$_{1-x}$Gd$_x$Cu$_2$O$_{8+\delta}$ single crystals is investigated by magnetic relaxation and hysteresis measurements. By substituting $Ca$ with $Gd$, it is found that the interlayer Josephson coupling…
Using the high-sensitive mechanical method of measuring the dissipation processes in superconductors, the 3D-2D phase transition in magnetic field was investigated in the vortex lattice of strongly anisotropic high-temperature…
We study the vortex phase diagram of the single-layer Bi2Sr2CuO6+d (Bi2201) superconductor by means of bulk magnetization measurements on high-quality oxygen-overdoped crystals. In striking contrast with the results found in the…
Precision measurements of the vortex phase diagram in single crystals of the layered superconductor Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ in oblique magnetic fields confirm the existence of a second phase transition, in addition to the…