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Article
Superfluid Density and Vortex Dynamics in S/F/S Heterostructures
We present electrical transport measurements in the microwave range in Superconductor/Ferromagnet/ Superconductor Nb/Pd 0.84Ni 0.16/Nb heterostructures, with different thickness of the ferromagnetic layer. We emp...
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Article
Directional Vortex Pinning at Microwave Frequency in YBa2Cu3O7−x Thin Films with BaZrO3 Nanorods
We investigate the effect of the anisotropy and of the directional pinning in YBa2Cu3O7−x films grown by pulsed laser ablation from targets containing BaZrO3 at 5 mol%. BaZrO3 inclusions ...
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Article
Superconducting and Structural Properties of Nb/PdNi/Nb Trilayers
The superconducting and structural properties of S/F/S (Superconductor/Ferromagnet/Superconductor) heterostructures have been studied by means of microwave measurements (1–20 GHz) and x-ray absorption fine str...
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Article
Microwave Properties of Nb/PdNi/Nb Trilayers
We combine wideband (1–20 GHz) Corbino Disk and Dielectric Resonator (8.2 GHz) techniques to study the microwave properties in Nb/PdNi/Nb trilayers, grown by UHV dc magnetron sputtering, composed by Nb layers ...
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Article
Vortex Motion and Quasiparticle Resistivity in MgB2 at Microwave Frequencies
The electrical transport in superconductors at nonzero frequencies is affected by the normal and superfiuid fractions, as well as moving vortices, resulting in intricate expressions for the complex resistivity...
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Article
Vortex State Microwave Resistivity in Tl-2212 Thin Films
We present measurements of the field induced changes in the 47 GHz complex resistivity, Δρ~(H, T), in Tl2Ba2CaCu2O8+x (TBCCO) thin films with T c ...
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Article
Dielectric Resonators for the Measurement of Superconductor Thin Films Surface Impedance in Magnetic Fields at High Microwave Frequencies
We present the design and realization of cylindrical dielectric resonators operating in the 40–60 GHz frequency range, designed for the measurement of the surface resistance and of the surface reactance shift ...
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Article
Mixed-State Microwave Response in Superconducting Cuprates
We report measurements of the magnetic field induced microwave complex resistivity in REBa2Cu3O7−δ thin films, with RE = Y, Sm. Measurements are performed at 48 GHz by means of a resonant cavity in the end-wall-r...
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Article
Substrate Contribution to the Surface Impedance of HTS Films on Si
We study the effects of semiconductor substrates on the surface impedance of high-T c Superconductor (HTS) YBa2Cu3O7−δ (YBCO) films. The characteristic impedanc...
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Article
High-Frequency Fluctuational Conductivity in YBa2Cu3O7−δ
We present measurements of the fluctuational excess conductivity at 48 GHz and 24 GHz in YBa2Cu3O7−δ films above the transition temperature. The measurements depart from the gaussian prediction for finite-frequen...
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Article
Field Dependent Microwave Resistivity in YBa2Cu3O7−δ
We investigate the effects of directional pinning due to the layered structure and to columnar defects on the microwave response in YBa2Cu3O7−δ films. We present measurements of the field-induced microwave resist...
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Article
Resistivity Tensor in the Normal State of BSCCO Single Crystals as a Function of Do**
We present measurements of the resistivity tensor of Bi2Sr2CaCu2O8+δ single crystals with different oxygen concentrations. Sample do** varies from underdoped to slightly overdoped. Measurements are performed th...
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Article
Fluctuative Conducitivity at Microwave Frequencies in BSCCO Thin Films
Measurements of the real part of the resistivity at 23 and 48 GHz are performed in Bi 2 Sr 2 CaCu 2 ...
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Article
Flux Flow and Fluctuation Resistivity at 48 GHz in High-T c Superconductors
We present measurements of the real part of the microwave resistivity at 48 GHz in YBa 2 Cu 3 O 7−δ ...