相关论文: Critical current scaling and anisotropy in oxypnic…
To understand the anisotropy of flux pinning and critical current density in technological superconductors, the scaling law for the anisotropy of single-vortex collective pinning in uniaxial superconductors is extended to flux-bundle…
The angular-dependent critical current density, Jc(theta), and the upper critical field, Hc2(theta), of epitaxial Ba(Fe1-xCox)2As2 thin films have been investigated. No Jc(theta) peaks for H || c were observed regardless of temperatures and…
Upper critical field parallel to the conducting layer is studied in anisotropic type-II superconductors on square lattices. We assume enough separation of the adjacent layers, for which the orbital pair-breaking effect is suppressed for…
Resistivity and magnetization have been measured at different temperatures and magnetic fields in organic superconductors $\kappa$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Br. The lower critical field and upper critical field are determined, which…
The field-angular dependence and anisotropy of the critical current density in iron-based superconductors is evaluated using a phenomenological approach featuring distinct anisotropy factors for the penetration depth and the coherence…
The upper critical field of multiband superconductors is an important quantity that can reveal the details about the nature of the superconducting pairing. Here we experimentally map out the complete upper critical field phase diagram of a…
We show on a few examples of one-band materials with spheroidal Fermi surfaces and anisotropic order parameters that anisotropies $\gamma_H$ of the upper critical field and $\gamma_\lambda$ of the London penetration depth depend on…
The dependence of the superconducting gaps in epitaxial Ba(Fe_{1-x}Co_{x})_2As_2 thin films on the nominal doping x (0.04 \leq x \leq 0.15) was studied by means of point-contact Andreev-reflection spectroscopy. The normalized conductance…
Superconducting technology provides most sensitive field detectors, promising implementations of qubits and high field magnets for medical imaging and for most powerful particle accelerators. Thus, with the discovery of new superconducting…
We report on the anisotropy of the vortex motion surface impedance of a \fst thin film grown on a CaF$_2$ substrate. The dependence on the magnetic field intensity up to 1.2 T and direction, both parallel and perpendicular to the sample…
To probe manifestations of multiband superconductivity in oxypnictides, we measured the angular dependence of the magnetic torque $\tau(\theta)$ in the mixed state of LaO$_{0.9}$F$_{0.1}$FeAs single crystals as a function of temperature $T$…
The newly found superconductivity in infinite-layer nickelate superconducting films has attracted much attention, because their crystalline and electronic structures are similar to high-$T_c$ cuprate superconductors. The upper critical…
The upper critical field of multi-band superconductors can be an essential quantity to unravel the nature of superconducting pairing and its interplay with the electronic structure. Here we experimentally map out the complete upper critical…
Dissipation-free current transport in high-temperature superconductors is one of the most crucial properties of this class of materials which is directly related to the effective inhibition of flux line movement by defect structures. In…
We study the effects of anisotropic order parameters on the temperature dependence of London penetration depth anisotropy $\gamma_\lambda(T)$. After MgB$_2$, this dependence is commonly attributed to distinct gaps on multi-band Fermi…
An increasing current through a superconductor can result in a discontinuous increase in the differential resistance at the critical current. This critical current is typically associated either with breaking of Cooper-pairs (de-pairing) or…
The in- and out-of-plane lower critical fields and magnetic penetration depths for LiFeAs were examined. The anisotropy ratio $\gamma_{H_{c1}}(0)$ is smaller than the expected theoretical value, and increased slightly with increasing…
Detailed measurements of the in-plane resistivity were performed in a high-quality Ba(Fe$_{1-x}$Co$_{x}$)$_2$As$_2$ ($x=0.065$) single crystal, in magnetic fields up to 9 T and with different orientations $\theta$ relative to the crystal…
We studied $ab$-plane transport properties in single crystals of the superconductor $\beta$-FeSe up to 16 T. In the normal state, below 90 K, the crystals present a strongly anisotropic positive magnetoresistance that becomes negligible…
Superconducting critical currents $j_{c} > 10^{5}$ A/cm$^{2}$ at temperatures $T \sim 50$ K and magnetic fields $B \sim 6$ T are reported for the YBa$_{2}$Cu$_{3-x}$Mo$_{x}$O$_{7+d}$ compound with $x = 0.02$. Clear evidence for the…