Incomplete devil's staircase in the magnetization curve of SrCu2(BO3)2

TL;DR

This study investigates the magnetization behavior of SrCu2(BO3)2, revealing a sequence of plateaus and incommensurate phases, and proposes that its magnetization process resembles an incomplete devil's staircase.

Contribution

It provides detailed NMR and torque measurements showing magnetization plateaus and incommensurate phases, introducing the concept of an incomplete devil's staircase in this material.

Findings

Identification of magnetization plateaus at 1/8, 2/15, 1/6, and 1/4 of saturation

Discovery of incommensurate phases around the 1/6 plateau

Stripe order of triplets in all plateaus

Abstract

We report on NMR and torque measurements on the frustrated quasi-two-dimensional spin-dimer system SrCu2(BO3)2 in magnetic fields up to 34 T that reveal a sequence of magnetization plateaus at 1/8, 2/15, 1/6, and 1/4 of the saturation and two incommensurate phases below and above the 1/6 plateau. The magnetic structures determined by NMR involve a stripe order of triplets in all plateaus, suggesting that the incommensurate phases originate from proliferation of domain walls. We propose that the magnetization process of SrCu2(BO3)2 is best described as an incomplete devil's staircase.