Pressure-induced shift of effective Ce valence, Fermi energy and phase boundaries in CeOs₄Sb₁₂

Journal article

CeOs4Sb12, a member of the skutterudite family, has an unusual semimetallic low-temperature L-phase that inhabits a wedge-like area of the field H - temperature T phase diagram. We have conducted measurements of electrical transport and megahertz conductivity on CeOs4Sb12 single crystals under pressures of up to 3 GPa and in high magnetic fields of up to 41 T to investigate the influence of pressure on the different H-T phase boundaries. While the high-temperature valence transition between the metallic H-phase and the L-phase is shifted to higher T by pressures of the order of 1 GPa, we observed only a marginal suppression of the S-phase that is found below 1 K for pressures of up to 1.91 GPa. High-field quantum oscillations have been observed for pressures up to 3.0 GPa and the Fermi surface of the highfield side of the H-phase is found to show a surprising decrease in size with increasing pressure, implying a change in electronic structure rather than a mere contraction of lattice parameters. We evaluate the field-dependence of the effective masses for different pressures and also reflect on the sample dependence of some of the properties of CeOs4Sb12 which appears to be limited to the low-field region

Authors: Götze, K; Pearce, MJ; Coak, MJ; Goddard, PA; Grockowiak, AD

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IOP Publishing
• Journal: New Journal of Physics
• Volume: 24
• Issue: 4
• Pages: 043044-043044
• Publication date: 2022-04-29
• DOI: 10.1088/1367-2630/ac643c
• EISSN: 1367-2630
• ISSN: 1367-2630
• Language: English
• Keywords: Quantum mechanics; Phase (matter); Valence (chemistry); Diamond anvil cell; Phase transition; Condensed matter physics; Thermodynamics; Phase diagram; Physics; High pressure