Fragile structural transition in Mo3Sb7

Abstract

Mo${}_3$Sb${}_7$ single crystals lightly doped with Cr, Ru, or Te are studied in order to explore the interplay between superconductivity, magnetism, and the cubic-tetragonal structural transition. The structural transition at 53\,K is extremely sensitive to Ru or Te substitution which introduce additional electrons, but robust against Cr substitution. No sign of a structure transition was observed in superconducting Mo${}_{2.91}$Ru${}_{0.09}$Sb${}_7$ and Mo${}_3$Sb${}_{6.975}$Te${}_{0.025}$. In contrast, 3at\% Cr doping only slightly suppresses the structural transition to 48\,K while leaving no trace of superconductivity above 1.8\,K. Analysis of magnetic properties suggests that the interdimer interaction in Mo${}_3$Sb${}_7$ is near a critical value and essential for the structural transition. All dopants suppress the superconductivity of Mo${}_3$Sb${}_7$. The tetragonal structure is not necessary for superconductivity.

6 pages, 5 figures, to appear in Phys. Rev. B

References in corpus (3)

• Frustration-induced valence bond crystal and its melting in Mo3Sb7
• Superconductivity of Mo3Sb7 from first principles
• Effect of the tetragonal distortion on the electronic structure, phonons and superconductivity in the Mo3Sb7 superconductor

Cited by in corpus (3)

• Flux growth in a horizontal configuration: an analogue to vapor transport growth
• Electron-phonon coupling and thermal transport in the thermoelectric compound $\mathrm{M}{\mathrm{o}}_3\mathrm{S}{\mathrm{b}}_{7-\mathrm{x}}\mathrm{T}{\mathrm{e}}_{\mathrm{x}}$
• Competition of superconductivity with the structural transition in Mo3Sb7