Study on the magnetic properties of ${\mathrm{Y}_{2-x}\mathrm{Bi}_{x}\mathrm{Ir}_{2}\mathrm{O}_{7}}$ by ${\mu}$SR and DC susceptibility

Pyrochlore iridates have received considerable attention recently as they possess strong electron correlation and spin orbit coupling, giving rise to a finite temperature metal-insulator transition (MIT). The nature of this MIT transition is related to the magnetic order of the Ir atoms which also experience frustration. By doping ${\mathrm{Y}_{2}\mathrm{Ir}_{2}\mathrm{O}_{7}}$ with Bi we are trying to elucidate the magnetic configuration of the iridium ions. Here we present a study on the magnetic properties of the ${\mathrm{Y}_{2-x}\mathrm{Bi}_{x}\mathrm{Ir}_{2}\mathrm{O}_{7}}$ system using ${\mu}$SR and DC susceptibility. Our results show that pure ${\mathrm{Y}_{2}\mathrm{Ir}_{2}\mathrm{O}_{7}}$ has a magnetic transition to long-range order. Substituting the Bi by Y results in a lower temperature transition with a less homogeneous spin-glass like order with increasing {\it x}. We will show the resulting magnetic phase diagram for this system to understand how its magnetic properties behave near the metal insulator phase boundary.