Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, NSW 2522, Australia.
J Phys Condens Matter. 2010 Apr 7;22(13):135701. doi: 10.1088/0953-8984/22/13/135701. Epub 2010 Mar 12.
This paper demonstrates the magnetic scattering effects on the electron-phonon interaction in two-band superconductors based on the transition-metal-doped MgB₂ to clarify the effects of magnetic dopants on multi-band superconductivity. The phonon properties of polycrystalline Mg(1-x)M(x)B₂ (M = Fe, Ni and Co), with x up to 0.05, were studied, with the investigation based on the normal state Raman spectra, especially the variation of the E(2g) mode. The magnetic scattering effect of Fe is much weaker than that of Mn in MgB₂, while it is stronger than that of Ni. The weak magnetic scattering effects are responsible for the superconducting behaviors of Mg(1 - x)Fe(x)B₂ and Mg(1 - x)Ni(x)B₂. Co shows almost no magnetic scattering effects on the superconductivity, while the depression of the critical temperature, T(c), in Mg(1 - x)Co(x)B₂ is attributed to the phonon behavior and is independent of the ferromagnetic nature of cobalt.
本文基于过渡金属掺杂的 MgB₂，研究了双带超导体中电子-声子相互作用的磁散射效应，以阐明磁性掺杂剂对多带超导性的影响。研究了多晶 Mg(1-x)M(x)B₂（M=Fe、Ni 和 Co，x 高达 0.05）的声子性质，基于正常态拉曼光谱，特别是 E(2g)模式的变化。Fe 的磁散射效应比 MgB₂中的 Mn 弱，但比 Ni 强。较弱的磁散射效应是 Mg(1 - x)Fe(x)B₂和 Mg(1 - x)Ni(x)B₂超导行为的原因。Co 对超导性几乎没有磁散射效应，而 Mg(1 - x)Co(x)B₂中临界温度 T(c)的降低归因于声子行为，与钴的铁磁性无关。
