Ale Crivillero, M. V., N. Haberkorn, G. Nieva, and J. Guimpel. "Electrical transport properties of FeSe/Fe3O4 bilayers." Materials Today: Proceedings 14 (2019): 18–21.
Abstract: In this work, we study the electronic properties of FeSe/Fe3O4 bilayers deposited onto SrTiO3 (100) and MgO (100) substrates by DC magnetron sputtering. The comparative study of Fe3O4 films grown on SrTiO3 and MgO reveals significant differences in the intensity of the Verwey transition (Tv∼130K). This allows us to probe the impact of the distortions associated to the Verwey transition on the transport properties of the FeSe over-layer in the FeSe/Fe3O4 bilayers. A correlated increase in the resistance and weakened superconducting properties are observed..
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Daudin, B. "Thermal conductivity of amorphous La70Cu30." Solid State Communications 37, no. 2 (1981): 149–152.
Abstract: We have measured in a temperature range of 0.6 to 6.5 K the thermal conductivity of various samples of amorphous La70Cu30 prepared by ultra rapid quenching. Below the superconducting critical temperature (Tc=3.85K) we found the classical amorphous behaviour and determined the coupling constant n0M2. Above Tc we found that the thermal conductivity was governed by the electron-phonon interaction and we discuss the results obtained.
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Decca, R., E. Osquiguil, F. de la Cruz, C. D'Ovidio, M. T. Malachevski, and D. Esparza. "Non linear temperature dependence of the resistivity of LaSrCuO: Effects of Sr content." Solid State Communications 69, no. 4 (1989): 355–357.
Abstract: The linear temperature dependence of the electrical resistivity has been taken to be one of the characteristic features of the ceramic superconductors. Measurements of the electrical resistance of the LaSrCuO system in a wide temperature range show that the previous statement is only an approximation valid for some values of the Sr concentration.
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Decca, R. S., H. D. Drew, B. Maiorov, J. Guimpel, and E. J. Osquiguil. "Inducing superconductivity at a nanoscale: Photodoping with a near- field scanning optical microscope." Journal of Microscopy 194, no. 2-3 (1999): 407–411.
Abstract: The local modification of an insulating GdBa2Cu3O6.5 thin film, made superconducting by illumination with a near-field scanning optical microscope (NSOM), is reported. A 100-nm aperture NSOM probe acts as a sub- wavelength light source of wavelength ?(exc)=480-650 nm, locally generating photocarriers in an otherwise insulating GdBa2-Cu3O6.5 thin film. Of the photogenerated electron-hole pairs, electrons are trapped in the crystallographic lattice, defining an electrostatic confining potential to enable the holes to move. Reflectance measurements at ? = 1.55 ?m at room temperature show that photocarriers can be induced and constrained to move on a ?? 200 nm scale for all investigated ?(exc). Photogenerated wires present a superconducting critical temperature T(c) = 12 K with a critical current density J(c) = 104 A cm-2. Exploiting the flexibility provided by photodoping through a NSOM probe, a junction was written by photodoping a wire with a narrow (? 50 nm) under-illuminated gap. The strong magnetic field modulation of the critical current provides a clear signature of the existence of a Josephson effect in the junction.
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Decca, R. S., H. D. Drew, E. Osquiguil, B. Maiorov, and J. Guimpel. "Anomalous proximity effect in underdoped YBa2Cu3O6+x Josephson junctions." Physical Review Letters 85, no. 17 (2000): 3708–3711.
Abstract: Experiments were carried out to probe the underdoped insulating material by the Josephson effect. Junctions were fabricated by exploiting the capability of locally photodoping insulating RBa2Cu3O6+x (R = rare earth) material. The existence of an anomalously large proximity effect was confirmed. The critical current of the junctions was consisted with the conventional Josephson relationship.
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Dolz, M. I., D. E. Shalóm, H. Pastoriza, and D. O. López. "Anisotropic response of the moving vortex lattice in superconducting Mo(1−x)Gex amorphous films." Physica C: Superconductivity 474 (2012): 34–37.
Abstract: We have performed magnetic susceptibility measurements in Mo(1−x)Gex amorphous thin films biased with an electrical current using anisotropic coils. We tested the symmetry of the vortex response changing the relative orientation between the bias current and the susceptibility coils. We found a region in the DC current–temperature phase diagram where the dynamical vortex structures behave anisotropically. In this region the shielding capability of the superconducting currents measured by the susceptibility coils is less effective along the direction of vortex motion compared to the transverse direction. This anisotropic response is found in the same region where the peak effect in the critical current is developed. On rising temperature the isotropic behavior is recovered.
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Esquinazi, P., and F. de la Cruz. "Phonon thermal conductivity limited by electron scattering in amorphous Zr70Cu30." Physical Review B 27, no. 5 (1983): 3069–3072.
Abstract: The low-temperature thermal conductivity of amorphous Zr70Cu30 is investigated. The lattice thermal conductivity as limited by electrons in the superconducting state has been obtained at temperatures close to Tc. This has allowed for the first time the verification of the temperature dependence of the phonon conductivity as predicted by Bardeen, Rickayzen, and Tewordt. The analysis of the data in the normal and superconducting state shows that Matthiessen's rule can be used in amorphous metals to separate the different scattering processes.
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Franco, D. G., A. Sarmiento-Chavez, N. Schenone, A. E. L. Allcca, M. G. Berisso, Y. Fasano, and J. Guimpel. "Characterization of the Nb-B Superlattice System." Physica C: Superconductivity and its Applications 531 (2016): 93–97.
Abstract: Abstract
We study the growth, stacking and superconducting properties of Nb and B thin films and superlattices. The interest in these resides in their possible use in transition edge neutron sensors. The samples were grown by magnetron sputtering over Si (100) substrates. The X-ray diffraction patterns for all Nb containing samples show a Nb (110) preferential orientation. From the low-angle X-ray reflectivity we obtain information on the superlattice structure. The superconducting transition temperatures of the superlattices, obtained from the temperature dependence of the magnetization, are higher than those of single Nb films of similar thickness. The temperature dependence of the perpendicular and parallel upper critical fields indicate that the superlattices behave as an array of decoupled superconducting Nb layers.
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Giriat, G., Z. Ren, P. Pedrazzini, and D. Jaccard. "High pressure investigation of superconducting signatures in CeCu2Si2: ac-magnetic susceptibility, ac-heat capacity, resistivity and thermopower." Solid State Communications 209–210 (2015): 55–58.
Abstract: Taking advantage of a novel multiprobe setup we have measured, on a unique sample, the ac-magnetic susceptibility, the resistivity, the ac-specific heat and the thermopower of the superconductor heavy fermion CeCu2Si2 under pressure up to 5.1 GPa. At the superconducting transition temperature Tc, the Meissner signal corresponds to that expected for the sample volume and coincides with the specific heat jump and the resistive transition completion temperatures. Differing from previous observations, here the susceptibility measurements did not reveal any anomaly in the vicinity of the resistive transition onset.
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Gonzalez, E. M., Z. Sefrioui, B. Maiorov, E. Osquiguil, and Santamar. "Effects of structural microdomains on the vortex correlation length in a-axis oriented EuBa2Cu3O7 thin films." Journal of Physics and Chemistry of Solids 67, no. 1-3 (2006): 399–402.
Abstract: We have grown a-axis oriented EuBa2Cu3O7 thin films on SrTiO3 (001) substrates using a magnetron sputtering technique. In these films the CuO2 planes are aligned parallel to the substrates. The film microstructure shows microdomains. The microdomains are grains with a 90
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