Phase transition in the 5d1 double perovskite Ba2CaReO6 induced by high magnetic field

TL;DR

This study reveals a magnetic field-induced phase transition in Ba2CaReO6 at around 50 T, highlighting strong coupling between electronic and lattice degrees of freedom in a 5d1 double perovskite.

Contribution

It demonstrates a high magnetic field-induced phase transition in Ba2CaReO6, showing the interplay between spin-orbit coupling, magnetic order, and lattice effects in this material.

Findings

Phase transition occurs at ~50 T with magnetization jump

Magnetostriction change indicates strong electron-lattice coupling

High field phase has a magnetic moment of ~0.2 μB

Abstract

Magnetic properties of an antiferromagnetic double perovskite oxide Ba2CaReO6, where Re6+ (5d1) ions with large spin-orbit coupling are arranged on the face-centered-cubic lattice, are investigated using pulsed high magnetic field up to 66 T. Magnetization and magnetostriction measurements have revealed a magnetic field induced phase transition at around 50 T. The phase transition accompanies a jump of magnetization and longitudinal magnetostriction of approximately 2 10^(-4) with the change of power law behavior, indicating sizable coupling between the electronic degrees of freedom and the lattice. The high field phase exhibits a magnetic moment approximately 0.2 {\mu}B, which is close to the values observed in 5d1 double perovskite oxides with non-collinear magnetic structure. We argue that Ba2CaReO6 is an antiferromagnet that sits close to the phase boundary between the collinear and non-collinear phases, providing the target material for investigating the interplay between spin-orbital entangled electrons and magnetic field.