paper

Ground-states of the Shastry-Sutherland Lattice Materials Gd $_{2}$ Be $_{2}$ GeO $_{7}$ and Dy $_{2}$ Be $_{2}$ GeO $_{7}$

arXiv:2505.04868

Abstract

The recent realization that the rare-earth melilites RE $_{2}$ Be $_{2}$ GeO $_{7}$ host the Shastry-Sutherland lattice within planes of RE $^{3 +}$ ions has sparked a number of studies. This family of materials lacks appreciable site mixing and conductivity, making them promising candidates for the Shastry-Sutherland model. Herein, we present the magnetic ground states of two of these rare-earth melilites: RE = Gd and Dy. We find, through measurements of magnetic susceptibility, magnetization, and specific heat capacity (RE = Dy only), that these two melilites are antiferromagnets (T $_{N}$ $\sim$ ~1~K). Gd $_{2}$ Be $_{2}$ GeO $_{7}$ , in accordance with its electronic configuration, has isotropic single-ion anisotropy but shows a quadratic contribution to its magnetization. Dy $_{2}$ Be $_{2}$ GeO $_{7}$ has Ising-like single-ion ansiotropy and is likely an effective spin- $1/2$ system. Both materials exhibit metamagnetic transitions. We identify this transition in Dy $_{2}$ Be $_{2}$ GeO $_{7}$ , occurring at 86(1)~mT for T=500~mK, to likely be a spin-flip transition.

11 pages, 7 figures, 1 table

Ground-states of the Shastry-Sutherland Lattice Materials Gd2​Be2​GeO7​ and Dy2​Be2​GeO7​

Abstract

Ground-states of the Shastry-Sutherland Lattice Materials Gd $_{2}$ Be $_{2}$ GeO $_{7}$ and Dy $_{2}$ Be $_{2}$ GeO $_{7}$