相关论文: Lower Critical Fields of Superconducting PrFeAsO$_…

In this article, we review our recent studies of microwave penetration depth, lower critical fields, and quasiparticle conductivity in the superconducting state of Fe-arsenide superconductors. High-sensitivity microwave surface impedance…

Anisotropic superconducting properties including the upper critical field Hc2, thermal activation energy U0, and critical current density Jc are systematically studied in a large Ca1-xLaxFeAs2 single crystal (x ~ 0.18). The obtained Hc2…

We investigate the temperature dependence of the lower critical field Hc1(T) of a high-quality FeSe single crystal under static magnetic fields H parallel to the c axis. The temperature dependence of the first vortex penetration field has…

The newly discovered iron-based superconductors have stimulated enormous interests in the field of superconductivity. Since the new superconductor is a layered system, the anisotropy is a parameter with the first priority to know. Meanwhile…

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 $T$…

Anisotropic properties of single crystals of SrPt$_{3}$P were studied using London penetration depth and electrical resistivity measurements. The upper critical field, $H_{c2}(T)$, was determined from four-probe electrical resistivity…

The upper critical fields, $H_{c2}$($T$), of single crystals of the superconductor Ca$_{10}$(Pt$_{4-\delta}$As$_{8}$)((Fe$_{0.97}$Pt$_{0.03}$)$_{2}$As$_{2}$)$_{5}$ ($\delta$ $\approx$ 0.246) are determined over a wide range of temperatures…

Since the discovery of high-temperature superconductivity, studying the upper critical field and its anisotropy has been crucial for understanding superconducting mechanism and guiding applications. Here we perform in situ high-pressure…

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…

Single crystals of the oxypnictide superconductor SmFeAsO_(0.8)F_(0.2) with T_c=45(1) K were investigated by torque magnetometry. The crystals of mass~0.1 mug were grown by a high-pressure cubic anvil technique. The use of a high-sensitive…

The temperature dependence of the upper critical magnetic field (Hc2) in a BaFe1.84Co0.16As2 single crystal was determined via resistivity, for the inter-plane (H^ab) and in-plane (H//ab) directions in pulsed and static magnetic fields of…

The anisotropic superconducting properties of single crystals of Cu0.07TiSe2 were studied by measurements of magnetization and electrical resistivity. TC is around 3.9 K, and the measured upper critical field (Hc2) values are ~1.25 T and…

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 present a detailed study of the electrical transport properties of a recently discovered iron-based superconductor: Sm$_4$Fe$_2$As$_2$Te$_{0.72}$O$_{2.8}$F$_{1.2}$. We followed the temperature dependence of the upper critical field by…

Superconductivity of Ca1-xLaxFe2As2 single crystals with various doping level were investigated via electromagnetic measurements for out-plane (H//c) and in-plane (H//ab) directions. Obvious double superconducting transitions, which can…

Single crystals of the oxypnictide superconductors SmFeAsO_(0.8)F_(0.2) and NdFeAsO_(0.8)F_(0.2) with T_c in the range of 44 K to 48 K were investigated by torque magnetometry. An analysis of the data in terms of a recently proposed model…

Single crystals of the LnFeAsO (Ln1111, Ln = Pr, Nd, and Sm) family with lateral dimensions up to 1 mm were grown from NaAs and KAs flux at high pressure. The crystals are of good structural quality and become superconducting when O is…

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…

Optimally-doped La1.85Sr0.15CuO4 single crystals have been investigated by dc and ac magnetic measurements. These crystals have rectangular needle-like shapes with the long needle axis parallel to the crystallographic c axis (c-crystal) or…

To investigate a mysterious superconducting state of URu_2Si_2 embedded in the so-called hidden order state, the lower critical field H_{c1} is precisely determined down to 55 mK for H || a and H || c. For this purpose, the positional…