Doping Induced Magnetization Plateaus

TL;DR

This paper investigates how doping antiferromagnetic spin chains with mobile carriers induces tunable magnetization plateaus at high magnetic fields, revealing a direct relation between carrier concentration and magnetization levels.

Contribution

It introduces an exactly solvable model demonstrating doping-induced magnetization plateaus and analyzes their critical behavior at the plateau edges.

Findings

Magnetization plateaus occur at fractions determined by carrier concentration

Plateaus are stable over a wide range of doping levels

Critical behavior at plateau edges is characterized in detail

Abstract

The low temperature magnetization process of antiferromagnetic spin-S chains doped with mobile spin-(S-1/2) carriers is studied in an exactly solvable model. For sufficiently high magnetic fields the system is in a metallic phase with a finite gap for magnetic excitations. In this phase which exists for a large range of carrier concentrations x the zero temperature magnetization is determined by x alone. This leads to plateaus in the magnetization curve at a tunable fraction of the saturation magnetization. The critical behaviour at the edges of these plateaus is studied in detail.