Effect of Pr substitution on the valence transition in Ce_1-_xPr_xOs₄Sb₁₂

At low temperatures T, the filled skutterudite CeOs₄Sb₁₂ is a heavy-fermion compensated semimetal and exhibits a Spin-Density-Wave (SDW) phase at ~1 K. Theoretical predictions suggested that it possibly possesses topologically protected states where electron and hole Fermi surfaces (FS) may coexist at low temperatures. Through previous studies of this compound, we’ve found that a near spherical FS above 28 T, enchantment of cyclotron mass below 35 T, and a valence transition occurs with a striking reverse wedge-shape T-H phase diagram [1,2,3]. When substituting the rare-earth element Pr for Ce, hole-doping is introduced in CeOs₄Sb₁₂. In this report, we present the influence of Pr-substitution on the electronic properties, T-H phase boundaries of the valence transition, and carrier density in Ce_1xPr_xOs₄Sb₁₂ (x = 0.1 and 0.2).

Refs: [1] K. Götze et. al, New J. Phys. 24, 043044 (2022). [2] K. Götze et. al, PRB 101, 075102 (2020). [3] P.-C. Ho et. al, PRB 94, 205140 (2016).