High-resolution resonant magnetic x-ray scattering on TbNi2B2C: Determination of the modulation wave vector in the orthorhombic phase - art. no. 104507

Resonant magnetic x-ray scattering measurements have been performed on a si ngle crystal of TbNi2B2C to uniquely determine the modulation wave vector i n the low-temperature orthorhombic phase. Below the transition temperature of 14.4(+/-0.1) K, two magnetic satellite peaks develop, centered on (h0)(o rth) charge reflections. Our study shows that the longitudinal modulation o f the magnetic moment is along, the longer basal plane axes of the orthorho mbic phase. Power law fits to the temperature dependence of the structural distortion, a/b-1, and the magnetic scattering intensity result in the same exponent, beta, and transition temperature evidencing explicitly that the structural phase transition is magneto-elastic in origin.