Magnetization measurements of nearly ferromagnetic compounds TiBe 2-xMx (M = Cu, Ag, Au, Fe) in low and high fields

Abstract

°R ésumé. 2014 Nous observons une croissance monotone de la susceptibilité des composés TiBe2-xCux avec la concentration du cuivre. Des mesures de l'aimantation à 1,24 K et 4,17 K dans des champs atteignant 213 kOe sont analysées à l'aide du formalisme de Landau des transitions de phase. La concentration critique pour le ferromagnétisme, xc, est de l'ordre de 0,2. L'introduction des solutés Ag et Au diminue la susceptibilité de TiBe2 (résultats préliminaires). Dans les composés TiBe2-xFex le moment magnétique du fer paraît être inférieur à 0,01 03BCB.

Thermal expansion and spin density fluctuations in TiBe2-xCu x itinerant ferromagnets

“…At each concentration, thermal expansion, magnetostriction [15] and magnetization measurements were all done on one and the same sample. The magnetization results were in good agreement with previous work [10][11][12][13][14]. The alloys are somewhat magnetically inhomogeneous, as can be seen from low field curvature in the Arrott plots for T > T~.…”

“…The alloys are somewhat magnetically inhomogeneous, as can be seen from low field curvature in the Arrott plots for T > T~. In addition, the coefficient y (the slope (M/m)/m2 in the Arrott plots) is field dependent, as was remarked by Acker et al [12].…”

“…TiBe2 is a strongly enhanced paramagnet and TiBe2-xCux alloys show properties typical of itinerant ferromagnets above a critical composition x ~ 0.15 [10][11][12][13][14]. Samples with x = 0, 0.16, 0.20 and 0.24 were prepared using the same technique as described by Smith [13] and were each in the form of a small cylinder cut from the centre of a melted and annealed button.…”