相关论文: Fully anisotropic superconducting transition in io…
We present an exhaustive analysis of transport measurements performed in twinned YBa2Cu3O7 single crystals which stablishes that the vortex solid-liquid transition is first order when the magnetic field H is applied at an angle theta away…
It is shown that the large effect of heavy ion-irradiation on the thermodynamical properties of the anisotropic superconductor YBa$_{2}$Cu$_{3}$O$_{7-\delta}$ extends well into the superconducting fluctuation regime. The presence of the…
Using large scale Monte Carlo simulations on a uniformly frustrated 3DXY model, we report a first order vortex lattice melting transition in clean, isotropic extreme type-II $\kappa \to \infty$ superconductors. This work clarifies an…
Sub-nanovolt resolution longitudinal and Hall voltages are measured in an ultra pure YBa2Cu3O7-d single crystal. The Hall anomaly and the first-order vortex-lattice melting transition are observed simultaneously. Changes in the dynamic…
In a type II superconductor in a moderate magnetic field, the superconductor to normal state transition may be described as a phase transition in which the vortex lattice melts into a liquid. In a biaxial superconductor, or even a uniaxial…
Superconductors have two key characteristics. They expel magnetic field and they conduct electrical current with zero resistance. However, both properties are compromised in high magnetic fields which can penetrate the material and create a…
We have investigated the magnetic phase diagram of a fully oxygenated detwinned YBa2Cu3O7 single crystal by means of magneto-caloric and magnetization measurements, and found thermodynamic evidence for a temperature dependent first-order…
A vortex lock-in transition was directly detected by torque magnetometry in an overdoped YBa2Cu3O7 single crystal of low anisotropy (\approx 7). The locked-in state was observed below the 3D to 2D crossover temperature Tcr = 76 K,…
We present magnetic susceptibility and electrical transport measurements of the highly anisotropic compound LaSb$_2$ observing a very broad transition into a clean, consistent with type-I, superconducting state with distinct features of 2…
Muon spin rotation measurements of the magnetic field distribution in the vortex state of the oxygen deficient high-Tc superconductor YBa{2}Cu{3}O{6.60} reveal a vortex-lattice melting transition at much lower temperature than that in the…
The vortex-liquid and vortex-solid phases in single crystals of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ placed in tilted magnetic fields are studied by in-plane resistivity measurements using the Corbino geometry to avoid spurious surface…
A superconducting transition in the temperature dependence of the ab-plane resistivity of underdoped YBa_2Cu_3O_{6+x} crystals in the range T_c<30 K has been investigated. Unlike the case of samples with the optimal level of doping, the…
Imaginary part of the microwave conductivity \sigma''(T<T_c) and the resistivity \rho(T)=1/\sigma(T>T_c) along (\sigma_{ab}'' and \rho_{ab}) and perpendicular to (\sigma_c'' and \rho_c) cuprate ab-planes of YBa_2Cu_3O_{7-x} crystal were…
The superconducting transition in a single overdoped, detwinned YBa2Cu3Ox (YBCO) crystal is studied using four different probes. Whereas the AC and DC magnetic susceptibilities find a dominant transition at 88 K with a smaller effect near…
Superconductivity of YBa$_2$Cu$_3$O$_{7-\delta}$ single crystals was investigated in small magnetic fields. In magnetic measurements the superconducting transition for $\textbf{H} \| c$ appears 0.4 K higher than for $\textbf{H} \bot c$. In…
The $c$-axis resistivity measurements in YBa_2Cu_4O_8 from Hussey et al. for magnetic field orientations along the c-axis as well as within the ab-plane are analyzed and interpreted using the scaling theory for static and dynamic classical…
The magnetization and anisotropic electrical transport properties have been measured in high quality Cu0.03TaS2 single crystal. A pronounced peak effect has been observed, indicating that the high quality and homogeneity are vital to peak…
A scan of the superconductor -- nonsuperconductor transformation in single crystals YBa_2Cu_3O_{6+x} (x about 0.37) was done in two alternative ways, namely, by applying the magnetic field and by reducing the hole concentration through the…
Explorations of the order-disorder transformation in vortex matter in single crystals of tetragonal structured (c/a $\sim$3) borocarbide superconductors, $YNi_2B_2C$ and $LuNi_2B_2C$, reveal that vortex arrays experience different effective…
In the quest to realize a quantum spin liquid (QSL), magnetic long-range order is hardly welcome. Yet it can offer deep insights into a complex world of strong correlations and fluctuations. Much hope was placed in the cubic pyrochlore…