相关论文: Enhanced current flow through meandering and tilte…

We present a set of experimental results concerning the power spectrum of current noise, detected on a granular high Tc superconductor submitted either to a slowly varying magnetic field or to a varying current intensity. Experiments were…

Thin films of the iron-based superconductor BaFe2(As1-xPx)2 (Ba122:P) were fabricated on polycrystalline metal-tape substrates with two kinds of in-plane grain boundary alignments (well aligned (4 deg.) and poorly aligned (8 deg.)) by…

In this paper, we present a detailed investigation of the self-field transport properties of an ionic liquid gated ultra-thin YBa$_2$Cu$_3$O$_{7-x}$ film. From the high temperature dynamic of the resistivity ($> 220 \textrm{ K}$) different…

Flux pinning is still the main limiting factor for the critical current of the high-temperature superconductors in high fields. In this paper we model the field dependence of the critical current in thin films with columnar defects aligned…

We have fabricated a series of ex situ copper sheathed powder-in-tube MgB2 wires with 20% by volume Ag, Pb, In, and Ga metal added to the MgB2 powder. We find the transport critical current of these wires increases significantly with the…

We report on the growth and characterization of ultrathin YBa$_2$Cu$_3$O$_{7-\delta}$ (YBCO) films on MgO (110) substrates, which exhibit superconducting properties at thicknesses down to 3 nm. YBCO nanowires, with thicknesses down to 10 nm…

Scanning superconducting quantum interference device measurements reveal large-scale modulations of the superfluid density and the critical temperature in superconducting Nb, NbN, and underdoped $YBa_{2}Cu_{3}O_{7-{\delta}}$ films deposited…

We discuss predictions of five proposed theories for the critical state of type-II superconductors accounting for both flux cutting and flux transport (depinning). The theories predict different behaviours for the ratio $E_y/E_z$ of the…

By means of the linear dynamic conductivity, inductively measured on epitaxial films between 30mHz and 30 MHz, the transition line $T_g (B)$ to generic superconductivity is studied in fields between B=0 and 19T. It follows closely the…

Understanding what makes Bi$_2$Sr$_2$Ca$_1$Cu$_2$O$_x$ (Bi-2212) the only high critical current density ($J_c$), high temperature superconductor (HTS) capable of being made as a round wire (RW) is important intellectually because high $J_c$…

Our Rutherford backscattering spectrometry (RBS) study has found that concentrations up to 7 atomic percent of Rb and Cs can be introduced to a depth of ~700 A in MgB2 thin films by annealing in quartz ampoules containing elemental alkali…

The electromagnetic properties of type-II superconductors depend on vortices -- magnetic flux lines whose motion introduces dissipation that can be mitigated by pinning from material defects. The material disorder landscape is tuned by the…

The influence of anisotropy on the transport current in MgB$_2$ polycrystalline bulk samples and wires is discussed. A model for the critical current density is proposed, which is based on anisotropic London theory, grain boundary pinning…

In this letter, we report the first successful fabrication of dense, metal-clad MgB2 superconductor wires as well as the first demonstration of high transport Jc of greater than 36,000 A/cm2 in MgB2. The fabrication technique that we…

The B-T phase diagram for thin film YBa_2Cu_3O_7-d with B parallel to the superconducting layers has been constructed from GHz transport measurements to 150T. Evidence for a transition from a high T regime dominated by orbital effects, to a…

We report an investigation of current transport in Nb/Au/CaSrCuO/YBaCuO heterostructures including an antiferromagnetic interlayer (CaSrCuO). Epitaxial thin films of YBaCuO and CaSrCuO were grown by laser ablation on NdGaO substrates; the…

YBCO films were successfully prepared on biaxially textured Ag{110}<211> substrates by using pulsed laser deposition. X-ray diffraction results showed that the degree of preferential orientation of Ag{110}<211> substrates varied with…

We performed magneto-optical (MO) measurements on FeTe$_{0.5}$Se$_{0.5}$ thin films grown on LaAlO$_3$ (LAO) and Yttria-stabilized zirconia (YSZ) single-crystalline substrates. These thin films show superconducting transition temperature,…

We present harmonic generation measurements of the intrinsic nonlinear current density $j_2$ of YBa$_2$Cu$_3$O$_{7-\delta}$ (YBCO) films at temperatures close the $T_c$. Experiments on a range of different quality samples allow us to…

Striation of HTS coated conductors (CCs) as a way to reduce their magnetization AC losses has been the subject of intense research in the past years by several groups. While the principle of this approach is well understood, its practical…