Karunakar Kothapalli

Unusual signatures of the ferromagnetic transition in the heavy fermion compound UMn2Al20

Magnetic-susceptibility results for single crystals of the new cubic compounds UT{sub 2}Al{sub 20} (T=Mn, V, and Mo) are reported. Magnetization, specific-heat, resistivity, and neutron-diffraction results for a single crystal and neutron diffraction and inelastic spectra for a powder sample are reported for UMn{sub 2}Al{sub 20}. For T=V and Mo, temperature-independent Pauli paramagnetism is observed. For UMn{sub 2}Al{sub 20}, a ferromagnetic transition is observed in the magnetic susceptibility at T{sub c}=20 K. The specific-heat anomaly at T{sub c} is very weak while no anomaly in the resistivity is seen at T{sub c}. We discuss two possible origins for this behavior of UMn{sub 2}Al{sub 20}: moderately small moment itinerant ferromagnetism or induced local-moment ferromagnetism.

Characterization of Gold Crystallinity by Diffraction Methods

Morphologically, crystals can be euhedral, composed of flat faces on all sides; subhedral, not completely bounded by crystal faces; or anhedral, exhibiting no crystal faces at all. The adherence to an ordered, repeating arrangement of atoms within a crystal can be quite variable; as a result, a continuum from almost perfect to very poor order (coherency) can be found in natural crystals. The extent to which atoms are ordered is known as the degree of crystallinity. Some The term crystal is used in two related but distinct contexts in mineralogy. First, it is used to describe a mineral or other solid whose natural shape comprises flat planes that are arranged in a symmetric order. In other words, it is used to describe the morphology of a solid. The term crystal is also used to denote a regular and repeating arrangement of atoms in three dimensions. The macroscopic formation and geometry of a crystal are in large part the product of the microscopic atomic structure. Ultimately, it is the regular, repeating arrangement of atoms that makes a solid material a crystal.

Structural, electronic, magnetic, and thermal properties of single-crystalline UNi0.5Sb2

We studied the properties of the antiferromagnetic (AFM) UNi0.5Sb2 (TN \approx 161 K) compound in Sb-flux grown single crystals by means of measurements of neutron diffraction, magnetic susceptibility ({\chi}), specific heat (Cp), thermopower (S), thermal conductivity ({\kappa}), linear thermal expansion ({\Delta}L/L), and electrical resistivity ({\rho}) under hydrostatic pressures (P) up to 22 kbar. The neutron diffraction measurements revealed that the compound crystallizes in the tetragonal P42/nmc structure, and the value of the U-moments yielded by the histograms at 25 K is \approx 1.85 \pm 0.12 {\mu}B/U-ion. In addition to the features in the bulk properties observed at TN, two other hysteretic features centered near 40 and 85 K were observed in the measurements of {\chi}, S, {\rho}, and {\Delta}L/L. Hydrostatic pressure was found to raise TN at the rate of \approx 0.76 K/kbar, while suppressing the two low temperature features. These features are discussed in the context of Fermi surface and hybridization effects.

Collapsed tetragonal phase transition in LaRu2P2

The structural properties of LaRu

Complex conductivity of UTX compounds in high magnetic fields

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RF skin-depth measurement of UIrGe in high magnetic fields

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Single-crystal neutron diffraction studies on Ni-based metal-pnictide superconductor BaNi2As2

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Lattice and Magnetic Anisotropies in Uranium Intermetallic Compounds

under external pressure have been studied up to 14 GPa, employing high-energy x-ray diffraction in a diamond-anvil pressure cell. At ambient conditions, LaRu

Onset of magnetism stimulated by H absorption in UNiAl-UFeAl

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Effect of temperature on hybridization and magnetism in UPdSn and UCuSn

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