Response of local structure to electron doping and external magnetic field in CuIr₂S₄

Thiospinel CuIr₂S₄ possessing partially filled iridium 5d t2g manifolds exhibits a metal to insulator transition around 230 K accompanied by orbital and charge order and spin singlet dimerization [1]. Local fluctuating orbital degeneracy lifting (ODL) state, a precursor to the transition, was recently discovered in its high temperature metallic regime [2]. By utilizing high energy X-ray total scattering measurements at National Synchrotron Light Source II, we explore temperature evolution of the dimerized and ODL states from the local structure perspective upon their perturbation by external stimuli. Specifically, we will discuss the effects of electron doping, achieved via Zn/Cu substitution of up to 70% including superconducting compositions [3], and application of magnetic field of up to 5 T, and the implications for the properties.

[1] P. G. Radaelli et al., Nature 416, 155 (2002)

[2] E. S. Bozin et al, Nature Commun. 10, 3638 (2019)

[3] G. Cao et al, Phys. Rev. B 64, 214514 (2001)