71 research outputs found
Electrical resistivity across the tricriticality in itinerant ferromagnet
We investigate the discontinuous ferromagnetic phase diagram near tricritical
point in UCo 1-x Ru x Al compounds by electrical resistivity measurements.
Separation of phases in UCo 0.995 Ru 0.005 Al at ambient pressure and in UCo
0.990 Ru 0.010 Al at pressure of 0.2 GPa and disappearance of ferromagnetism at
0.4 GPa is confirmed. The exponent of temperature dependence of electrical
resistivity implies change from Fermi liquid behavior to non-Fermi liquid at
0.2 GPa and reaches minimum at 0.4 GPa. Our results are compared to results
obtained on the pure UCoAl and explanation for different exponents is given
Samarium Magnetism Studied on SmPd2Al3 Single Crystal
In this paper, specific features of Sm magnetism in an intermetallic compound
have been studied. For this purpose, a high-quality single crystal of SmPd2Al3
was grown and subjected to detailed measurements of specific heat,
magnetization, ac susceptibility, and electrical resistivity with respect to
temperature and a magnetic field applied along the principal crystallographic
directions. SmPd2Al3 magnetism was found to be strongly anisotropic with the
easy-magnetization direction along the c axis where the main magnetic features
are concentrated. The a-axis response remains weak, paramagneticlike, even in
the magnetically ordered state. Ferromagnetism with TC=12.4 K has been
indicated by all the measured physical properties. At lower temperatures, three
successive order-order phase transitions have been observed on the temperature
dependence of the specific heat as three anomalies: at 3.4, 3.9, and 4.4 K,
respectively. The low-temperature magnetization data can be understood within a
scenario that considers the antiferromagnetic ground state as being gradually
destroyed through a series of four metamagnetic transitions at 0.03, 0.35, 0.5,
and 0.75 T, as detected in the 1.8 K magnetization data. The experimental data
are discussed together with the results of electronic-structure and
crystal-field calculations from first principles, which were performed as an
important part of the study for comprehension and explanation of the observed
behavior of the SmPd2Al3 compound
Pressure Evolution of Magnetism in URhGa
In this paper, we report the results of an ambient and high pressure study of
a 5f-electron ferromagnet URhGa. The work is focused on measurements of
magnetic and thermodynamic properties of a single crystal sample and on the
construction of the p-T phase diagram. Diamond anvil cells were employed to
measure the magnetization and electrical resistivity pressures up to ~ 9 GPa.
At ambient pressure, URhGa exhibits collinear ferromagnetic ordering of uranium
magnetic moments {\mu}U ~ 1.1 {\mu}B (at 2 K) aligned along the c-axis of the
hexagonal crystal structure below the Curie temperature TC = 41K. With the
application of pressure up to 5GPa the ordering temperature TC initially
increases whereas the saturated moment slightly decreases. The rather
unexpected evolution is put in the context of the UTX family of compounds.Comment: arXiv admin note: text overlap with arXiv:1611.0327
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