Zur Supraleitung einiger Mischsysteme von Verbindungen mit A15-Struktur auf Niobbasis

Abstract

Solid solutions between the compounds Nb3A1, Nb3Ga, NbsGe, Nb3In, and Nb3Sn have been prepared by arc melting in argon atmosphere. Transitions to superconductivity, lattice constants and values of microhardness have been measured for all samples as cast as well as annealed. In agreement with MATTmAS et al. the highest transition to superconductivity at 20.05 ~ has been observed in the system Nb 3 (All_xGex). A relation between microhardness and transition to superconductivity also expressed by MATTmAS has been verified for most of the systems.

Superconductivity in Nb5Ir3−xPtxO

“…On the other hand, Nb 3 Sn provides the non monotonous substitution effect of T c , especially when the counterpart of end member is also a superconductor. For example, Nb 3 Sn 1−x In x , in which Nb 3 In is 5 K superconductor, shows the x independent T c up to x ∼0.12 [19]. So our study might indicate that two-gap superconductivity ascribed to the Nb atoms is rather robust against the atomic replacement other than Nb atom, if the counter part of end Nb-compound is also a superconductor.…”

Theoretical investigation of the mechanical and thermodynamics properties of Nb3Ga superconductor under pressure

“…It is noticed that 11 C , 12 C and 44 C increase almost linearly with applied pressure. It is also obvious that the constant 11 C varies largely under pressure as compared with the…”

“…A C C E P T E D ACCEPTED MANUSCRIPT 11 The Grüneisen parameter γ describes the anharmonic effects of the crystal lattice thermal vibration. The temperature-dependence of Grüneisen parameter γ of Nb 3 Ga at 0, 10, 20, 30 and 40 GPa are presented in Fig.…”

“…Superconductivity in Nb 3 Ga was first observed by Wood et al and its superconductivity transition temperature T c was 14.5 K [8]. Since then many scholars have measured the superconductivity transition temperature, the results show that the T c of the Nb 3 Ga varies from 14.5~20.7 K, depending on Nb/Ga ratio and long range ordering of the A15 crystal structure [9][10][11][12]. Vieland et al [13] synthesized Nb 3 Ga by chemical vapor deposition (CVD), and measured the T c =20.3 K.…”

Superconductivity of Nb3A1 base ternary solid solutions

“…gallium (1,2). In the unit cell of Nb A1 the equivalent positions 2(a) a r e occupied by aluminium atoms, while the niobium atoms a r e situated in the positions 6(c).…”