Competing Magnetic Phases on a "Kagome Staircase"

TL;DR

This paper investigates the complex magnetic phases of Ni_3V_2O_8 on a kagome staircase, revealing multiple incommensurate and commensurate phases driven by competing interactions and anisotropy.

Contribution

It provides detailed thermodynamic and neutron data on Ni_3V_2O_8, illustrating how subleading interactions induce order in a highly frustrated kagome system.

Findings

Identification of two incommensurate phases: amplitude modulated and helical.

Discovery of a low-temperature canted antiferromagnetic phase.

Phase diagram explained by competing first and second neighbor interactions.

Abstract

We present thermodynamic and neutron data on Ni_3V_2O_8, a spin-1 system on a kagome staircase. The extreme degeneracy of the kagome antiferromagnet is lifted to produce two incommensurate phases at finite T - one amplitude modulated, the other helical - plus a commensurate canted antiferromagnet for T ->0. The H-T phase diagram is described by a model of competing first and second neighbor interactions with smaller anisotropic terms. Ni_3V_2O_8 thus provides an elegant example of order from sub leading interactions in a highly frustrated system