# Coexistence of high electrical conductivity and weak ferromagnetism in Cr doped Y$_2$Ir$_2$O$_7$ pyrochlore iridate

## TL;DR

This study investigates how Cr doping in Y2Ir2O7 pyrochlore iridates enhances electrical conductivity and induces weak ferromagnetism, revealing complex magnetic interactions and valence state coexistence.

## Contribution

It provides new insights into the effects of Cr doping on the structural, magnetic, and electrical properties of Y2Ir2O7, including valence state changes and magnetic behavior.

## Key findings

- Cr doping significantly increases electrical conductivity.
- Cr doping induces weak ferromagnetism and a cluster-glass transition.
- Valence states of Ir coexist and are affected by Cr doping.

## Abstract

We report the structural, magnetic and electrical transport properties of Y$_2$Ir$_{2-x}$Cr$_x$O$_7$ pyrochlore iridates. The chemical doping leads to order of magnitude enhancement of electrical conductivity. The introduction of Cr3+ at Ir4+ site tends to distort the Ir-O6 octahedra and suppresses antiferromagnetic correlation. The X-ray photoemission spectroscopy measurements suggest the coexistence of Ir4+ and Ir5+ valence states in the Y$_2$Ir$_{2-x}$Cr$_x$O$_7$ compounds. The concentration of Ir5+ is enhanced with Cr doping, leading to weak ferromagnetism and enhanced electrical conductivity. A cluster-glass like transition is also observed at low temperature with Cr doping, possibly due to competing ferromagnetic and antiferromagnetic interaction.