Magnetization of SrCu2(BO3)2 in ultrahigh magnetic fields up to 118 T

TL;DR

This study investigates the magnetization behavior of SrCu2(BO3)2 in ultrahigh magnetic fields up to 118 T, revealing multiple magnetization plateaux and confirming the theoretical model with numerical simulations.

Contribution

It provides the first detailed experimental observation of high-field magnetization plateaux in SrCu2(BO3)2 and validates the Shastry-Sutherland model with specific exchange interaction ratios.

Findings

Observation of 1/2, 1/3, 1/8, 1/4 plateaux in magnetization.

Quantitative agreement with the Shastry-Sutherland model at J'/J=0.63.

Prediction of complex intermediate phases including supersolids.

Abstract

The magnetization process of the orthogonal-dimer antiferromagnet SrCu2(BO3)2 is investigated in high magnetic fields of up to 118 T. A 1/2 plateau is clearly observed in the field range 84 to 108 T in addition to 1/8, 1/4 and 1/3 plateaux at lower fields. Using a combination of state-of-the-art numerical simulations, the main features of the high-field magnetization, a 1/2 plateau of width 24 T, a 1/3 plateau of width 34 T, and no 2/5 plateau, are shown to agree quantitatively with the Shastry-Sutherland model if the ratio of inter- to intra-dimer exchange interactions J'/J=0.63. It is further predicted that the intermediate phase between the 1/3 and 1/2 plateau is not uniform but consists of a 1/3 supersolid followed by a 2/5 supersolid and possibly a domain-wall phase, with a reentrance into the 1/3 supersolid above the 1/2 plateau.