2019/07/31 by K. Götze, M. J. Pearce, Paul Goddard +13 · 11 citations
Chemistry · Materials Science · Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Chemistry #Condensed matter physics #Crystallography #Geometry #Inverse #Iron-based superconductors research #Mathematics #Phase (matter) #Phase boundary #Phase diagram #Phase transition #Physics #Quantum mechanics #Rare-earth and actinide compounds #Valence (chemistry) #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.101.075102
published in Physical review. B./Physical review. B 101(7) (American Physical Society) · 7 pages, 4 figures and Supplementary Information of 4 pages, 2 figures
openalex created_date 2019/07/30 · arxiv created 2019/11/29 · openalex publication_date 2020/02/03 · arxiv updated 2020/02/12 · openalex updated_date 2026/08/06
The phase diagram of the filled skutterudite CeOs4Sb12 has been mapped in fields \ensuremathμ0H of up to 60 T and temperatures T down to 0.5 K using resistivity, magnetostriction, and megahertz conductivity. The valence transition separating the semimetallic low-H, low-T L phase from the metallic high-H, high-T H phase exhibits a very unusual, wedge-shaped phase boundary, with a nonmonotonic gradient alternating between positive and negative. The expected ``elliptical'' behavior of the phase boundary of a valence transition with H2\ensuremath∝T2 originates in the H and T dependence of the free energy of the f multiplet. Here, quantum oscillation measurements suggest that additional energy scales associated with a quantum critical point are responsible for the deviation of the phase boundary of CeOs4Sb12 from this textbook behavior at high H and low T. The distortion of the low-H, high-T portion of the phase boundary may be associated with the proximity of CeOs4Sb12 to a topological semimetal phase induced by uniaxial stress.