Related papers: Vortex lock-in transition coinciding with the 3D t…
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…
In cuprate high-temperature superconductors the small coherence lengths and high transition termperatures result in strong thermal fluctuations, which render the superconducting transition in applied magnetic fields into a wide continuous…
The complex resistivity $\hat{\rho}(\omega)$ of the vortex lattice in an untwinned crystal of 93-K $\rm YBa_2Cu_3O_7$ has been measured at frequencies $\omega/2\pi$ from 100 kHz to 20 MHz in a 2-Tesla field $\bf H\parallel c$, using a…
To study the relationship between the properties of low-dimensional spin systems with weakly coupled Cu-triangles and their crystal structure, single crystals of $Cs_3Cu_3Cl_8OH$ (1) and the new $Cs_3Cu_3Cl_{7.6}Br_{0.4}OH$ (2) were grown.…
Trapped low magnetic flux dynamics including local ones are investigated in YBCO single crystals in the strong thermal fluctuations domain near the superconducting phase transition temperatures. The essential difference from…
Vortex trapping is investigated in thin-film strips of superconducting material. We present a model for the critical field above which vortex trapping occurs in these strips. This model includes the pairing energy of vortex-antivortex pairs…
Resistance in superconductors arises from the motion of vortices driven by flowing supercurrents or external electromagnetic fields and may be strongly affected by thermal or quantum fluctuations. The common expectation borne out in…
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…
Rattling-induced superconductivity in the {\beta}-pyrochlore oxide KOs2O6 is investigated under high pressure up to 5 GPa. Resistivity measurements in a high-quality single crystal reveal a gradual decrease in the superconducting transition…
Inverse melting, in which a crystal reversibly transforms into a liquid or amorphous phase upon decreasing the temperature, is considered to be very rare in nature. The search for such an unusual equilibrium phenomenon is often hampered by…
We report the synthesis of high-quality 2H-TaS2 nanowires via a controlled two-step conversion process from TaS3 precursors, achieving robust superconductivity with a transition temperature Tc ~ 3.6 K which is significantly higher than bulk…
We present our recent results on the temperature dependence of current-voltage characteristics for polycrystalline Y_{1-x}Pr_{x}Ba_2Cu_3O_7 superconductors with x = 0.0, 0.1 and 0.3. The experimental results are found to be reasonably well…
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…
We report that single crystals of (Ba,K)Fe2As2 with Tc = 32 K have a pinning potential, U0, as high as 10^4 K, with U0 showing very little field depend-ence. In addition, the (Ba,K)Fe2As2 single crystals become isotropic at low temperatures…
Investigations into the heterogeneous pinning properties of the vortex state created by partially nano-patterning single crystals of 2H-NbSe2 reveal an atypical magnetization response which is significantly drive dependent. Analysis of the…
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…
The copper oxides present the highest superconducting temperature and properties at odds with other compounds, suggestive of a fundamentally different superconductivity. In particular, the Abrikosov vortices fail to exhibit localized states…
We present here some striking discrepancies in the results of ac and dc magnetization measurements performed in a single crystal of low Tc superconductor, Yb3Rh4Sn13. Fingerprint of a transition from an ordered vortex lattice a la Bragg…
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…
Dynamics of vortices in strongly type-II superconductors with strong disorder is investigated within the frustrated three-dimensional XY model. For two typical models in [Phys. Rev. Lett. {\bf 91}, 077002 (2003)] and [Phys. Rev. B {\bf 68},…