Crystal Growth and Cylindrical Fermi Surfaces of USb₂

Abstract

We have grown high-quality single crystals of tetragonal USb 2 using a flux method. We have detected five branches in de Haas-van Alphen (dHvA) experiments. Frequencies of all dHvA branches follow the 1/ cos θ-dependence, revealing the presence of cylindrical Fermi surfaces, where θ is a tilt angle from [001] to [100]. The cyclotron masses are in the range from 1.84 to 8.33 m 0 . The two-dimensional Fermi surfaces are due to the electrons in the including the itinerant 5f -electrons.

Ligand and Actinide NMR Studies in Actinide Oxides and Intermetallic Compounds

“…For example, the temperature dependence of Knight shifts and the K-plots for the 69 Ga (2) For NpCoGa 5 the Knight shifts K i , where i is the field axis, increase in the paramagnetic state as temperature approaches T N . This temperature variation of K i scales with that of i , which obeys a modified Curie-Weiss law: ðTÞ ¼ 0 þ C=ðT À ÂÞ.…”

“…[67][68][69] In spite of the small gyromagnetic ratio n of 235 U nuclei (¼ 0:784 MHz/T), 70) the large HF field originating from the ordered moments enables us to observe a 235 U NMR signal under zero applied field. To our knowledge, this is the first observation of the 235 U NMR signal in an itinerant 5 f electron system, which follows the previous report of a 235 U NMR study on a localized 5 f electron system, UO 2 .…”

“…This is comparable to the observed magnetic susceptibility with H ext parallel to the c-axis of the crystal, obs ¼ 1:32 Â 10 À3 emu/mol. 69) Nonzero f is a characteristic feature of an itinerant system, where the magnitude of ordered moments originates from band polarization and may be substantially modified by an external field. Hence, our NMR measurements probe the itinerant character of the 5 f electrons in USb 2 , as suggested by other experimental results.…”

Anisotropy of Magnetic and Transport Properties οf UAuSb2Single Crystals

“…The de Haas-van Alfven (dHvA) experiments performed for this parent compound indicated the formation of the quasi-two-dimensional (QTD) electronic states, due to the layered character of this structure. It develops in the form of four kinds of nearly cylindrical Fermi surface pieces [2] for the magnetic field applied along the tetragonal [001] direction. In the case of UAuSb 2 , planes of gold atoms intercalate into the unit cell of USb 2 increasing considerable the ratio c/a from 2.05 to 2.25.…”

Surface structure of cleaved (001) USb2single crystal

“…It has a layered tetragonal structure that is easily cleaved and has been extensively studied by a number of different techniques, such as resistivity [6], Hall effect measurements [7], photoemission [8] and angle-resolved photoemission spectroscopy [9,10], de Haas-van Alphen [11][12][13], neutron diffraction [14], U 238 anti-ferromagnetic nuclear magnetic resonance [15], and U 238 Mossbauer spectroscopy [16] techniques. A great deal of information is already known about its structure and magnetic and electronic properties.…”