2020/03/31 by Pascal Reiss, Jordan Baglo, Hong En Tan +8
Chemistry · Materials Science · Physics and Astronomy · #Anisotropy #Chemistry #Condensed matter physics #Crystal structure #Crystallography #Fermi liquid theory #Fermi surface #Iron-based superconductors research #Isostructural #Physics #Quantum mechanics #Rare-earth and actinide compounds #Superconductivity #Superconductivity in MgB2 and Alloys #Valence (chemistry) #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.102.081102
published as Phys. Rev. B 102, 081102 (2020) · 6 pages, 4 figures
arxiv created 2020/03/31 · openalex created_date 2020/04/10 · openalex publication_date 2020/08/03 · arxiv updated 2020/08/12 · openalex updated_date 2026/08/05
The origin of intrinsic quantum criticality in the heavy-fermion superconductor \ensuremathβ\ensuremath-YbAlB4 has been attributed to strong Yb valence fluctuations and its peculiar crystal structure. Here, we assess these contributions individually by studying the isostructural but fixed-valence compound \ensuremathβ\ensuremath-LuAlB4. Quantum oscillation measurements and density functional theory calculations reveal a Fermi surface in \ensuremathβ\ensuremath-LuAlB4 markedly different from that of \ensuremathβ\ensuremath-YbAlB4, consistent with a ``large'' Fermi surface in the latter. We also find an unexpected in-plane anisotropy of the electronic structure, in contrast to the isotropic Kondo hybridization in \ensuremathβ\ensuremath-YbAlB4.