Anisotropic Magnetism in Gd$_2$B$_5$

We report the synthesis of single crystals of Gd$_2$B$_5$ through a ruthenium-gadolinium flux method. The Gd$_2$B$_5$ system is a member of the monoclinic $P21/c$ (No. 14) space group and realizes lattices of gadolinium atoms in the $(1\,0\,0)$ plane. We characterized the sample through orientation-dependent electrical transport, magnetization, magnetic torque, and heat capacity measurements to probe the magnetic anisotropy of the system and map out its phase diagram. Gd$_2$B$_5$ realizes two zero-field ordered phases M$_1$ and M$_2$, as well as a third field-induced ordered phase M$_\perp$ arising when the magnetic field is applied in the $(1\,0\,0)$ plane.