Magnetization, crystal structure and anisotropic thermal expansion of single-crystal SrEr2O4

The magnetization, crystal structure, and thermal expansion of a nearly stoichiometric Sr${}_{1.04(3)}$Er${}_{2.09(6)}$O${}_{4.00(1)}$ single crystal have been studied by PPMS measurements and in-house and high-resolution synchrotron X-ray powder diffraction. No evidence was detected for any structural phase transitions even up to 500 K. The average thermal expansions of lattice constants and unit-cell volume are consistent with the first-order Gr"uneisen approximations taking into account only the phonon contributions for an insulator, displaying an anisotropic character along the crystallographic \emph{a}, \emph{b}, and \emph{c} axes. Our magnetization measurements indicate that obvious magnetic frustration appears below $\sim$15 K, and antiferromagnetic correlations may persist up to 300 K.