Magnetic properties of van der Waals layered single crystals DyOBr and SmOCl

Two-dimensional van der Waals single crystals DyOBr and SmOCl have been grown by flux method and their anisotropic magnetic properties are reported. DyOBr orders antiferromagnetically at T\(_{N}\)=9.5 K with magnetic moments lying along \(a\)-axis, similar as DyOCl. Its magnetic susceptibility shows an anomaly at T\(^{*}\)=30 K possibly due to the crystal field effect. Furthermore a 1/3 magnetization plateau is clearly observed under H\(\parallel\)a and H\(\parallel\)[110], which might be a field-induced spin-flop phase or some exotic quantum magnetic state. On the other hand, isostructural SmOCl undergoes an antiferromagnetic transition at T\(_{N}\)=7.1 K and exhibits a contrasting Ising-like perpendicular \(c\)-axis magnetic anisotropy, which could be well explained by our crystal field calculations. Both DyOBr and SmOCl are insulators with band gap of \(\sim\)5 eV, our results suggest they are promising in building van der Waals heterostructures and applications in multifunctional devices.