Magnetization Plateaus by the Field-Induced Partitioning of Spin Lattices

TL;DR

This paper proposes that magnetization plateaus arise from field-induced partitioning of spin lattices into magnetic fragments, explaining why certain magnets exhibit plateaus, their types, and widths, based on how magnetic structures absorb Zeeman energy.

Contribution

It introduces the concept that magnetic field causes spin lattices to partition into magnetic fragments, providing a unifying explanation for magnetization plateaus.

Findings

Partitioning of spin lattices explains plateau formation.

Anisotropic magnetization supports the fragment hypothesis.

Width of plateaus relates to magnetic fragment stability.

Abstract

To search for a conceptual picture describing the magnetization plateau phenomenon, we surveyed the crystal structures and the spin lattices of those magnets exhibiting plateaus in their magnetization vs. magnetic field curves by probing the three questions: (a) why only certain magnets exhibit magnetization plateaus, (b) why there occur several different types of magnetization plateaus, and (c) what controls the widths of magnetization plateaus. We show that the answers to these questions lie in how the magnets under field absorb Zeeman energy hence changing their magnetic structures. The magnetic structure of a magnet insulator is commonly described in terms of its spin lattice, which requires the determination of the spin exchanges nonnegligible strengths between the magnetic ions. Our work strongly suggests that a magnet under magnetic field partitions its spin lattice into antiferromagnetic (AFM) or ferrimagnetic fragments by breaking its weak magnetic bonds. Our supposition of the field-induced partitioning of spin lattice into magnetic fragments is supported by the anisotropic magnetization plateaus of Ising magnets and by the highly anisotropic width of the 1/3-magnetization plateau in azurite. The answers to the three questions (a) - (c) emerge naturally by analyzing how these fragments are formed under magnetic field.