Element-specific field-induced spin reorientation and an unusual tetracritical point in MnCr2S4

TL;DR

This study reveals element-specific spin reorientations and uncovers an unusual tetracritical point in the magnetic phase diagram of MnCr2S4, highlighting complex magnetic interactions driven by spin-lattice coupling.

Contribution

It provides direct, element-resolved evidence of magnetic moment reorientations and identifies a novel tetracritical point in MnCr2S4 due to strong spin-lattice interactions.

Findings

Element-specific magnetic moment reorientations observed up to 40 T

Identification of an unusual tetracritical point in the phase diagram

Magnetocaloric measurements support complex magnetic structures

Abstract

The ferrimagnetic spinel MnCr2S4 shows a variety of magnetic-field-induced phase transitions owing to bond frustration and strong spin-lattice coupling. However, the site-resolved magnetic properties at the respective field-induced phases in high magnetic fields remain elusive. Our soft x-ray magnetic circular dichroism studies up to 40 T directly evidence element-selective magnetic-moment reorientations in the field-induced phases. The complex magnetic structures are further supported by entropy changes extracted from magnetocaloric-effect measurements. Moreover, thermodynamic experiments reveal an unusual tetracritical point in the H-T phase diagram of MnCr2S4 due to strong spin-lattice coupling.