Evolution of T2 resistivity and superconductivity in Nb3Sn under pressure

Pressure effect on the superconducting and the normal state of β−Bi2Pd

“…The mutual decrease of T c and A with pressure points to a close relationship between these quantities. This result is consistent with the studies of Nb 3 Sn [11,28], which show that T c is a function of N (E F ).…”

“…The latter model applied on the normal-state resistivity at increasing pressure provides evidence that the dominant phonon frequency is shifted higher and the electron-phonon coupling constant is decreasing upon increasing pressure causing a lower T c . The fits by the Bloch-Grüneisen model are affected by T 2 dependence of resistivity at low temperatures up to about 25 K, similarly as in Nb 3 Sn [11]. Evolution of this T 2 dependence of the resistivity under pressure we present in Sec.…”

“…10. Recently, Ren et al [11] observed very similar behavior of ρ(T ) in Nb 3 Sn. Their results highlighted the importance of the electronic states at the Fermi level and opened a question on the superconducting pairing in this material.…”

Anomalous Behavior in the Atomic Structure of Nb3Sn under High Pressure

“…These properties contributed to make Nb 3 Sn the most widely used high field superconductor in top science projects (CERN High luminosity LHC project [5], ITER [6] project) and industrial applications (NMR instruments, compact cyclotrons), with a record production in the period 2009-2014 of 150 Tons/Year for the ITER toroidal field magnets only [7]. The exceptional requirements of these magnet-based projects revamped the interest in this material and considerable efforts are now undertaken to further improve their critical performances and efficiencies during the applications [8][9][10]. In particular, the effects of strains (axial, transverse, hydrostatic) on J c , T c and the electrical resistivity, which may be caused by thermal contractions and strong Lorentz forces due to the high currents, were extensively explored [4,9,[11][12][13][14][15].…”

“…The exceptional requirements of these magnet-based projects revamped the interest in this material and considerable efforts are now undertaken to further improve their critical performances and efficiencies during the applications [8][9][10]. In particular, the effects of strains (axial, transverse, hydrostatic) on J c , T c and the electrical resistivity, which may be caused by thermal contractions and strong Lorentz forces due to the high currents, were extensively explored [4,9,[11][12][13][14][15]. However, less is known about the structural modifications induced by pressure, especially on the crystallographic and atomic scale [15][16][17].…”