ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Recent data suggest that ferromagnetic Ce compounds are only found for a restricted range of Ce-Ce distance1: 3.65 A(ring)≤d≤3.83 A(ring). This hypothesis will be compared to the "R-γ*'' correlation,2 which states that magnetic order can only occur when the electronic heat capacity coefficient γ*≥γ@B|m ≈3.5×104 erg cm−3 K2. Additional analysis suggests that, as a function of increasing γ*, weak ferromagnetism first occurs as γ* initially surpasses γ*m, yielding to antiferromagnetism at higher γ*. Materials such as URu2Si2 constitute evidence that a third region of spin-density-wave order preceeds that of ferromagnetism for γ*≈γ@B|m. Spin-density-wave order also competes with antiferromagnetism and coexists with heavy fermion superconductivity in the case of CeCu2Si2 and UPt3 (and possibly UBe13) in a narrow region about γ*≈1×105 erg cm−3 K2. The temporary stability of ferromagnetism may be explained by the wave-vector dependence of the electronic self-energy that is responsible for heavy fermion behavior.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.344617
