Recent studies in heavily hole-doped iron-based superconductor RbFe2As2 have suggested the emergence of novel electronic nematicity directed along the Fe-As direction, 45∘ rotated from the usual nematicity ubiquitously found in BaFe2As2 and related materials. This motivates us to study the physical properties of Ba1−xRbxFe2As2, details of which remain largely unexplored. Here we report on the normal-state charge transport in Ba1−xRbxFe2As2 superconductors by using high-quality single crystals in the range of Rb concentration 0.14≤x≤1.00. From the systematic measurements of the temperature dependence of electrical resistivity ρ(T), we find a signature of a deviation from the Fermi liquid behavior around the optimal composition, which does not seem related to the antiferromagnetic quantum criticality but has a potential link to hidden nematic quantum criticality. In addition, electron correlations derived from the coefficient of T2 resistivity show a marked increase with Rb content near the heavily hole-doped end, consistent with the putative Mott physics near the 3d5 electron configuration in iron-based superconductors.
@article{arxiv.2209.15526,
title = {Charge Transport in Ba$_{1-x}$Rb$_{x}$Fe$_{2}$As$_{2}$ Single Crystals},
author = {Masaya Tsujii and Kousuke Ishida and Shigeyuki Ishida and Yuta Mizukami and Akira Iyo and Hiroshi Eisaki and Takasada Shibauchi},
journal= {arXiv preprint arXiv:2209.15526},
year = {2022}
}