Unconventional pressure-driven metamagnetic transitions in topological van der Waals magnets

TL;DR

This study demonstrates pressure-induced metamagnetic transitions in topological van der Waals magnets, revealing complex pressure and temperature-dependent magnetic phase behavior that could advance spintronic applications.

Contribution

It uncovers how external pressure triggers multiple metamagnetic transitions in Mn(Bi$_{1-x}$Sb$_x$)$_4$Te$_7$, highlighting the interplay of interlayer couplings without chemical disorder.

Findings

Pressure enhances interlayer hopping without disorder.

Metamagnetic transitions show non-trivial pressure and temperature dependence.

Re-entrant magnetic phases observed under certain conditions.

Abstract

Activating metamagnetic transitions between ordered states in van der Waals magnets and devices bring great opportunities in spintronics. We show that external pressure, which enhances the interlayer hopping without introducing chemical disorders, triggers multiple metamagnetic transitions upon cooling in the topological van der Waals magnets Mn(Bi$_{1-x}$Sb$_x$)$_4$Te$_7$, where the antiferromagnetic interlayer superexchange coupling competes with the ferromagnetic interlayer coupling mediated by the antisite Mn spins. The temperature-pressure phase diagrams reveal that while the ordering temperature from the paramagnetic to ordered states is almost pressure-independent, the metamagnetic transitions show non-trivial pressure and temperature dependence, even re-entrance. For these highly anisotropic magnets, we attribute the former to the ordering temperature being only weakly dependent on the intralayer parameters, the latter to the parametrically different pressure and temperature dependence of the two interlayer couplings. Our independent probing of these disparate magnetic interactions paves an avenue for efficient magnetic manipulations in van der Waals magnets.