Magnetic transition and spin fluctuations in the unconventional antiferromagnetic compound Yb3Pt4
| Autor: | C. Marques, Meigan Aronson, Songrui Zhao, J. M. Mackie, Yuri Janssen, Oscar Bernal, D. E. MacLaughlin |
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| Jazyk: | angličtina |
| Rok vydání: | 2010 |
| Předmět: |
Physics
Condensed matter physics Strongly Correlated Electrons (cond-mat.str-el) Relaxation (NMR) Neutron diffraction FOS: Physical sciences Knight shift 02 engineering and technology Muon spin spectroscopy 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences chemistry.chemical_compound Condensed Matter - Strongly Correlated Electrons chemistry 0103 physical sciences Antiferromagnetism General Materials Science Condensed Matter::Strongly Correlated Electrons Fermi liquid theory 010306 general physics 0210 nano-technology Néel temperature AFm phase |
| Popis: | Muon spin rotation and relaxation measurements have been carried out on the unconventional antiferromagnet Yb_3Pt_4. Oscillations are observed below T_N = 2.22(1) K, consistent with the antiferromagnetic (AFM) Neel temperature observed in bulk experiments. In agreement with neutron diffraction experiments the oscillation frequency omega_ mu(T) follows a S = 1/2 mean-field temperature dependence, yielding a quasistatic local field 1.71(2) kOe at T = 0. A crude estimate gives an ordered moment of ~0.66 mu_B at T = 0, comparable to 0.81 mu_B from neutron diffraction. As T approaches T_N from above the dynamic relaxation rate lambda_d exhibits no critical slowing down, consistent with a mean-field transition. In the AFM phase a T-linear fit to lambda_d(T), appropriate to a Fermi liquid, yields highly enhanced values of lambda_d/T and the Korringa constant K_ mu^2 T/lambda_d, with K_ mu the estimated muon Knight shift. A strong suppression of lambda_d by applied field is observed in the AFM phase. These properties are consistent with the observed large Sommerfeld-Wilson and Kadowaki-Woods ratios in Yb_3Pt_4 (although the data do not discriminate between Fermi-liquid and non-Fermi-liquid states), and suggest strong enhancement of q ~ 0 spin correlations between large-Fermi-volume band quasiparticles in the AFM phase of Yb_3Pt_4. 11 pages, 4 figures, submitted to J. Phys.: Condens. Matter special issue for SCES10 |
| Databáze: | OpenAIRE |
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