Superconductivity in the spinels: Cu(Ir_{1-x}Pt_x)2Se4 and CuRh2S4

Spinels, which have formula AB2X4 and crystallise in the cubic space group, exhibit a rich landscape of structural, magnetic and electronic properties. However, superconducting compounds of this family have proven fairly elusive. Previous routes to reaching superconductivity is via substitution of the A ion, such as Cu-Zn substitution in CuIr2S4. The parent compound exhibits a metal-insulator transition, concomitant with a complex structural transition and a charge-ordered and spin-dimerised state. We propose to investigate an alternative pathway to superconductivity via substitution of the B ion. The systems we would like to study are prototypical examples of this and muons as sensitive local probes can give us important information about the electric, magnetic and superconducting properties, such as the pairing mechanism, which gives insights into the electro-structural coupling.