We report the results of thermodynamic measurements in external magnetic field of the cubic Ce-based cage compounds Ce
Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher.
Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
-
Abstract T 2Cd20(T = Ni,Pd). Our analysis of the heat-capacity data shows that the Γ7doublet is the ground state multiplet of the Ce3+ions. Consequently, for the Γ7doublet it can be theoretically shown that the Ruderman–Kittel–Kasuya–Yosida interaction between the localized Ce moments mediated by the conduction electrons, must vanish at temperatures much lower than the energy separating the ground state doublet from the first excited Γ8quartet. Our findings provide an insight as to why no long range order has been observed in these compounds down to temperatures in the milliKelvin range. -
Free, publicly-accessible full text available October 1, 2023
-
Abstract CeOs4Sb12, a member of the skutterudite family, has an unusual semimetallic low-temperature
-phase that inhabits a wedge-like area of the fieldH —temperatureT phase diagram. We have conducted measurements of electrical transport and megahertz conductivity on CeOs4Sb12single 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 differentH –T phase boundaries. While the high-temperature valence transition between the metallic -phase and the -phase is shifted to higherT by pressures of the order of 1 GPa, we observed only a marginal suppression of the -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 high-field side of the -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 CeOs4Sb12which appears to be limitedmore » -
Global perspectives of the bulk electronic structure of URu 2 Si 2 from angle-resolved photoemission
Abstract Previous high-resolution angle-resolved photoemission (ARPES) studies of URu2Si2have characterized the temperature-dependent behavior of narrow-band states close to the Fermi level (
E F) at low photon energies near the zone center, with an emphasis on electronic reconstruction due to Brillouin zone folding. A substantial challenge to a proper description is that these states interact with other hole-band states that are generally absent from bulk-sensitive soft x-ray ARPES measurements. Here we provide a more globalk -space context for the presence of such states and their relation to the bulk Fermi surface (FS) topology using synchrotron-based wide-angle and photon energy-dependent ARPES mapping of the electronic structure using photon energies intermediate between the low-energy regime and the high-energy soft x-ray regime. Small-spot spatial dependence,f -resonant photoemission, Si 2p core-levels, x-ray polarization, surface-dosing modification, and theoretical surface slab calculations are employed to assist identification of bulk versus surface state character of theE F-crossing bands and their relation to specific U- or Si-terminations of the cleaved surface. The bulk FS topology is critically compared to density functional theory (DFT) and to dynamical mean field theory calculations. In addition to clarifying some aspects of the previously measured high symmetry Γ,Z andX points, incommensurate 0.6a * nested Fermi-edge states located alongZ –N –Z are found to be distinctlymore »