Uranium moment collapse in magnetically diluted US

• Published in: Journal of magnetism and magnetic materials Vol. 205; no. 1; pp. 79 - 89
• Main Authors: Grosse, G, Kalvius, G.M, Kratzer, A, Schreier, E, Burghart, F.J, Mattenberger, K, Vogt, O
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.1999; Elsevier Science
• Subjects: Actinides; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Diamagnetism, paramagnetism and superparamagnetism; Exact sciences and technology; Local moment in compounds and alloys; kondo effect, valence fluctuations, heavy fermions; Localized moments; Magnetic phase boundaries (including magnetic transitions, metamagnetism, etc.); Magnetic properties and materials; Magnetic resonances and relaxations in condensed matter, mössbauer effect; Magnetically ordered materials: other intrinsic properties; Muon spin relaxation; Muon spin rotation; Muon spin rotation and relaxation; Physics; Muon spin relaxation; Muon spin rotation; Localized moments; 75.20.Hr; Actinides; Temperature dependence; Local magnetic moment; Inorganic compounds; Magnetic ordering; Ternary compounds; Actinide compounds; Uranium sulfides; Ferromagnetic materials; Magnetic moments; Composition effect; Rare earth compounds; Experimental study; Magnetic transitions; Monocrystals; Diamagnetic materials; Critical exponents; Lanthanum sulfides
• ISSN: 0304-8853
• DOI: 10.1016/S0304-8853(99)00467-9

Muon spin rotation/relaxation (μSR) measurements were carried out on single crystalline specimens of U x La 1− x S with x=1, 0.8, 0.55, 0.4, 0.15 and 0 in the temperature range between 300 and 0.1 K. The limiting compounds US and LaS are ferromagnetic and diamagnetic, respectively. In the pseudo-binary system a collapse of the U magnetic moment was observed in bulk magnetic and neutron diffraction studies at x<0.6. There neutrons no longer were able to detect magnetic order. Our μSR data verify the moment collapse below x=0.6 but show that it leads to weak (between 0.3 and 0.05 μ B), but not vanishing U moments. Furthermore, all componds except the diamagnetic LaS exhibit a magnetic transition with the transition temperature decreasing linearly with diminishing U content.