2005/05/14 by Eric Jobiliong, E. Jobiliong, J. S. Brooks +9
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Iron-based superconductors research #Other Condensed Matter (cond-mat.other) #Rare-earth and actinide compounds #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity in MgB2 and Alloys #cond-mat.other #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.cond-mat/0505362
24 pages, 12 figures, 1 table
arxiv created 2005/05/14 · openalex publication_date 2005/05/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Of the dense Kondo materials in the class CeTSb2 (where T = Au, Ag, Ni, Cu,\nor Pd), CeAgSb2 is special due to its complex magnetic ground state, which\nexhibits both ferro- and anti-ferromagnetic character below an ordering\ntemperature TO ~ 9.8 K. To further elucidate a description this magnetic ground\nstate, we have carried out a systematic study of single crystalline CeAgSb2 by\nmagnetic, electrical magneto-transport, and Shubnikov-de Haas (SdH) studies\nover a broad range of temperature and magnetic field. We have constructed the\nmagnetic phase diagram based solely on magnetoresistance data. Here, depending\non the orientation of the magnetic field H, either ferromagnetic or\nantiferromagnetic ordering occurs below TO. The resistivity of this compound\nbelow TO does not follow a simple Fermi liquid behavior, but requires an\nadditional contribution from conduction electron scattering from boson\nexcitations with an energy gap, D. At zero field the temperature dependent\nresistivity below TO is most consistent with antiferromagnetic order, based on\nthe transport theory which includes magnon scattering. Crystal field effect\ntheory applied to the susceptibility data yields splitting energies from the\nground state to the first and second excited states of 53 K and 137 K,\nrespectively. Although there is some uncertainty in the Kondo temperature\ndetermination, we estimate TK ~ 23 K from our analysis. In the Fermi surface\nstudies, the measurements show very small Fermi surface sections, not predicted\nby band structure calculations, and the SdH amplitudes are very sensitive to\nfield direction. Only by considering lens orbits between the main Fermi surface\ncylinders can the SdH results be reconciled with the Fermi surface topology\npredicted from band structure.\n