3 research outputs found
Physical properties of the new Uranium ternary compounds U3Bi4M3 (M=Ni, Rh)
We report the properties of two new isostructural compounds, U3Bi4Ni3 and
U3Bi4Rh3. The first of these compounds is non-metallic, and the second is a
nearly ferromagnetic metal, both as anticipated from their electron count
relative to other U-based members of the larger 3-4-3 family. For U3Bi4Rh3, a
logarithmic increase of C/T below 3 K, a resistivity proportional to T^4/3, and
the recovery of Fermi-liquid behavior in both properties with applied fields
greater than 3T, suggest that U3Bi4Rh3 may be a new example of a material
displaying ferromagnetic quantum criticality.Comment: 24 pages, 7 figures, submitted to Physical Review
Synthesis and Properties of CaFeAs Single Crystals
We report the synthesis and basic physical properties of single crystals of
CaFe2As2, an isostructural compound to BaFe2As2 which has been recently doped
to produce superconductivity. CaFe2As2 crystalizes in the ThCr2Si2 structure
with lattice parameters a = 3.907(4) A and c = 11.69(2) A. Magnetic
susceptibility, resistivity, and heat capacity all show a first order phase
transition at T_0 171 K. The magnetic susceptibility is nearly isotropic from 2
K to 350 K. The heat capacity data gives a Sommerfeld coefficient of 8.2 +- 0.3
mJ/molK2, and does not reveal any evidence for the presence of high frequency
(> 300 K) optical phonon modes. The Hall coefficient is negative below the
transition indicating dominant n-type carriers.Comment: Published version, minor change