The application of pressure as well as the successive substitution of Ru with Fe in the hidden order (HO) compound URu2Si2 leads to the formation of the large moment antiferromagnetic phase (LMAFM). Here we have investigated the substitution series URu2−xFexSi2 with x = 0.2 and 0.3 with non-resonant inelastic x-ray scattering (NIXS) and 4f core-level photoelectron spectroscopy with hard x-rays (HAXPES). NIXS shows that the substitution of Fe has no impact on the symmetry of the ground-state wave function. In HAXPES we find no shift of spectral weight that would be indicative for a change of the 5f-electron count. Consequently, changes in the exchange interaction J due to substitution must be minor so that the conjecture of chemical pressure seems unlikely. An alternative scenario is discussed, namely the formation of long range magnetic order due the substitution induced local enhancement of the magnetization in the vicinity of the f-electron ions while the overall electronic structure remains unchanged.
@article{arxiv.2005.03946,
title = {Impact of Fe substitution on the electronic structure of URu$_2$Si$_2$},
author = {Martin Sundermann and Andrea Amorese and Daisuke Takegami and Hlynur Gretarsson and Hasan Yavaş and Andrei Gloskovskii and Christoph Schlueter and Sheng Ran and M. Brian Maple and Peter Thalmeier and Liu Hao Tjeng and Andrea Severing},
journal= {arXiv preprint arXiv:2005.03946},
year = {2020}
}