相关论文: Critical current density and ac harmonic voltage g…
In this investigation we report the determination of the critical current density $J_c$ flowing in a $\mathrm{Y}\mathrm{Ba}_2\mathrm{Cu}_3\mathrm{O}_{7-\delta}$ superconducting thin film. Estimation of $J_c$ was carried out by an inductive…
Detailed measurements of the critical current density jc of YBa2Cu3O7 films grown by pulsed laser deposition reveal the increase of jc as function of the filmthickness. Both this thickness dependence and the field dependence of the critical…
The generation of harmonics of the voltage response is considered when an AC current is applied through a superconducting film above T_c. It is shown that almost at all temperatures the mechanism of the temperature oscillations created by…
We have applied the mutual inductive method to study higher-order harmonics of complex ac susceptibility $\chi_n=\chi'_n-i\chi"_n$ for $$YB_2C_3O_{7-\delta}$ thin films as function of the temperature and the applied field. The experimental…
We report on measurements of higher harmonics of the ac voltage response in strips of YBa2Cu3O7 thin films as a function of temperature, frequency and ac current amplitude. The third (fifth) harmonic of the local voltage is found to exhibit…
We have measured magnetic response of second-generation high temperature superconductor YBa2Cu3Ox wire and Nb thin film in perpendicular ac field as a function of temperature. We compare experimental complex ac susceptibility to the…
Temperature dependence of the zero-field critical current density, Jc0(T), in the CuO2 planes has been investigated for c-axis oriented YBa2Cu3O7-d (Y123) thin films with different hole content, p. p-values were varied by changing the…
Using the Green's function of the 3D heat equation, we develop an analytical account of the thermal behaviour of superconducting films subjected to electrical currents larger than their critical current in the absence of an applied magnetic…
Most measurements of critical current densities in YBa$_2$Cu$_3$O$_{7-\delta}$ thin films to date have been performed on films where the \textit{c}-axis is grown normal to the film surface. With such films, the analysis of the dependence of…
We report on the thickness dependence of the superconducting characteristics including critical current Ic, critical current density Jc, transition temperature Tc, irreversibility field Hirr, bulk pinning force plot Fp(H), and the normal…
In this paper, we report on the sharp peak observed in the third harmonic voltage response generated by a bias sinusoidal current applied to several strips patterned in a YBa2Cu3O7-d thin film and in two La1-xSrxCuO4 thin films, when the…
Mechanisms of vortex dynamics and pinning and self-field effects which could account for the thickness dependence of the critical current density J_c of superconducting films are addressed. It is shown that at low magnetic fields B, the 2D…
Numerical models for computing the effective critical current of devices made of HTS tapes require the knowledge of the Jc(B,theta) dependence, i.e. of the way the critical current density Jc depends on the magnetic flux density B and its…
The temperature behaviour of the first critical field ($B_{C1}$) of superconducting thin film samples can be determined with high accuracy using an inductive and contactless method. Driving a sinusoidal current in a single coil placed in…
We report on the temperature-dependent optical response of thin films of YBa2Cu3O7-{\delta} (YBCO) in the visible spectral range under cryogenic conditions. Specifically, we observe an increase in transmittance near the superconducting…
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…
Current-voltage characteristics of top seeded melt-textured YBa2Cu3O7-d are presented. The samples were cut out of centimetric monoliths. Films characteristics were also measured on microbridges patterned on thin films grown by dc…
Critical current measurements were made on thin films of YBa2Cu3O7-delta and Y0.8Ca0.2Ba2Cu3O7-delta produced by sol-gel and pulsed laser deposition, respectively. Both samples have high critical currents at low temperatures and the…
The critical current (Jc) of highly twinned YBa2Cu3O7 films has been measured as a function of temperature, magnetic field and angle. For much of the parameter space we observe a strong suppression of Jc for fields in the twin boundary (TB)…
The critical current density of a superconducting film can be easily determined by an inductive and contactless method. Driving a sinusoidal current in a single coil placed in front of a superconducting sample, a non zero third harmonic…