Residual resistivity

About: Residual resistivity is a research topic. Over the lifetime, 1912 publications have been published within this topic receiving 27140 citations.

Critical fields, Pauli paramagnetic limiting, and material parameters of Nb 3 Sn and V 3 Si

Abstract: The upper-critical-field behavior of ${\mathrm{Nb}}_{3}$Sn and ${\mathrm{V}}_{3}$Si is studied as a function of residual resistivity. The results are analyzed in the framework of the Ginzburg-Landau-Abrikosov-Gor'kov theory of type-II superconductivity including the effects of the electron-phonon interaction. The importance of the electron-phonon interaction on the Pauli paramagnetic limiting process is stressed and it is found that inclusion of the electron-phonon corrections (most importantly the electron-phonon renormalization of the normal-state parameters) is needed to sensibly fit the data. For ${\mathrm{Nb}}_{3}$Sn failure to include these effects leads to too high spin-orbit scattering rates. The critical-field data are also used to determine the density of states of these materials as well as several other superconducting and normal-state parameters.

Proper scaling of the anomalous Hall effect.

Abstract: Working with epitaxial films of Fe, we succeeded in independent control of different scattering processes in the anomalous Hall effect. The result clearly exposed the fundamental flaws of the conventional scaling rhoAH=f(rho(xx)) between the anomalous Hall resistivity and longitudinal resistivity. A new scaling rhoAH=f(rho(xx0),rho(xx)) that also involves the residual resistivity has been established which helps identify the intrinsic and extrinsic mechanisms of the anomalous Hall effect.

Superconductivity in MgB2: clean or dirty?

Abstract: A large number of experimental facts and theoretical arguments favor a two-gap model for superconductivity in MgB2 However, this model predicts strong suppression of the critical temperature by interband impurity scattering and, presumably, a strong correlation between the critical temperature and the residual resistivity No such correlation has been observed We argue that this fact can be understood if the band disparity of the electronic structure is taken into account, not only in the superconducting state, but also in normal transport

Temperature dependence of spin diffusion length and spin Hall angle in Au and Pt

Abstract: We have studied the spin transport and the spin Hall effect as a function of temperature for platinum (Pt) and gold (Au) in lateral spin valve structures. First, by using the spin absorption technique, we extract the spin diffusion length of Pt and Au. Secondly, using the same devices, we have measured the spin Hall conductivity and analyzed its evolution with temperature to identify the dominant scattering mechanisms behind the spin Hall effect. This analysis confirms that the intrinsic mechanism dominates in Pt whereas extrinsic effects are more relevant in Au. Moreover, we identify and quantify the phonon-induced skew scattering. We show that this contribution to skew scattering becomes relevant in metals such as Au, with a low residual resistivity.

Superconducting properties and crystal structures of single‐crystal niobium nitride thin films deposited at ambient substrate temperature

Abstract: Single‐crystal niobium nitride (NbN) thin films were fabricated at ambient substrate temperature so that photoresist lift‐off techniques could be used in fabricating Josephson tunnel junctions In this article, we describe the superconducting properties and crystal structure of the NbN films Even though the substrates were not heated, the NbN films had excellent superconducting properties: a high Tc of 16 K, low normal‐state resistivity (ρ20=62 μΩ cm), and residual resistivity ratios RRR=ρ300/ρ20 above one The film structures, which were investigated by x‐ray diffraction, electron diffraction patterns and transmission electron micrographs, show a single‐phase orientation without columnar and granular structures We have found that the superconducting properties depend on the lattice parameter, and the best films had a lattice parameter of 0446 nm NbN/AlN/Nb tunnel junctions were fabricated to measure the superconducting energy gap of the NbN films We estimated the energy gap ΔNbN to be 26 meV and th