Synthesis and magnetic properties of the Shastry-Sutherland family <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>R</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Be</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>SiO</mml:mi><mml:mn>7</mml:mn></mml:msub></mml:mrow><mml:mo> </mml:mo><mml:mrow><mml:mo>(</mml:mo><mml:mi>R</mml:mi><mml:mo>=</mml:mo><mml:mi>Nd</mml:mi><mml:mo>,</mml:mo><mml:mi>Sm</mml:mi><mml:mo>,</mml:mo><mml:mtext>Gd-Yb</mml:mtext><mml:mo>)</mml:mo></mml:mrow></mml:math>
A. Brassington, Qing Huang, A. A. Aczel, Haidong Zhou
Abstract
Compounds forming the quasi-two-dimensional Shastry-Sutherland lattice (SSL) have attracted significant experimental and theoretical attention in the field of frustrated magnetism. This is primarily due to their realization of an exactly soluble ${J}_{1}\text{\ensuremath{-}}{J}_{2}$ orthogonal dimer model capable of hosting magnetic order, dimer singlet, and plaquette singlet phases in zero applied field and their complex magnetic phase diagrams with fractional magnetization plateaus and possible superfluid and supersolid phases found between the plateau states. The discovery and characterization of SSL compounds based on rare-earth magnetic ions provide a direct route to study the stability and properties of these exotic magnetic phases in systems with a variety of different magnetic anisotropies. In this paper, we discuss the synthesis and magnetic characterization of polycrystalline samples of the ${R}_{2}{\mathrm{Be}}_{2}{\mathrm{SiO}}_{7}$ family, where $R=\mathrm{Nd}$, Sm, and Gd-Yb. All family members crystallize in the space group $P\overline{4}{2}_{1}m$ (113) and show no signs of long-range magnetic order above 2 K, except for $R=\mathrm{Tb}$ which orders antiferromagnetically at 2.6 K.