Effect of Magnetic Phase Transition on the Electronic Specific Heat Coefficient of Lu(Co_1−xAl_x)₂

Abstract

The low temperature specific heat of Lu(Co, -xAlx)z is measured between 1.4 and 6.5 K. The electronic specific heat coefficient, y, is enhanced around the critical concentration for the onset of ferromagnetism, while it is sharply reduced in a ferromagnetic region with a substantial moment. The results are discussed in relation with the magnetism in this system. Die spezifische Warme von Lu(Co, -xAlx)z bei niedrigen Temperaturen wird zwischen 1 , 4 und 6,5 K gemessen. Der elektronische Koeffzient der spezifischen Warme y, ist in der Nahe der kritischen Konzentration fur den Einsatz von Ferromagnetismus erhoht, wahrend er in einem ferromagnetischen Bereich mit einern betrachtlichen Moment stark reduziert ist. Diese Ergebnisse werden bezuglich des Magnetismus in diesem System diskutiert. IndroductionRecently, the C15 Laves phase compounds Lu(Co, -,AQ2 have been found to show interesting magnetic behaviour. LuCo, is a well-known compound as a strongly exchangeenhanced Pauli paramagnet with a maximum in the susceptibility versus temperature curve [l]. By the substitution of A1 for Co, the susceptibility increases and the system shows an I ) Sakyo-ku, Kyoto 606, Japan.

Magnetic and electrical properties of RCo2Mn (R=Ho, Er) compounds

“…The values of g reported in the literature vary from 34 to 36.5 mJ mol À 1 K À 2 for YCo 2 and 26.7 to 36.5 mJ mol À 1 K À 2 for LuCo 2 . The values reported for y D are in the range of 226-305 K for YCo 2 and 238-280 K for LuCo 2 [4,[14][15][16][17][18][19][20]. By using the values of y D = 250 K and g=26 mJ mol À 1 K À 2 , we have calculated the nonmagnetic contribution to the heat capacity in the present case and a reasonable agreement has been obtained for the low temperature (ToT C ) regime.…”

Onset of magnetism in Y1 xGdxCo2: effect on the heat capacity and electrical resistivity

“…It should be noted that a non-monotonic change of ρ res , γ and D with maxima around the critical concentration for the appearance of the long-range magnetic order was also observed for the Lu(Co 1−x M x ) 2 and Y(Co 1−x M x ) 2 compounds [33][34][35][36] at the partial substitution of M(=Al, Ga) atoms for Co. In our opinion, the presence of such anomalies in these systems is also associated with the influence of LSF.…”

Magnetovolume effects in metamagnetic itinerant-electron systems and

“…Therefore, the variation of n dd will correlate with that of γ . The γ -values of Lu(Co 1−x Ga x ) 2 and Y(Co 1−x Al x ) 2 are plotted as functions of x in figure 7, together with those of Lu(Co 1−x Al x ) 2 for comparison [6,26,27]. With increasing x, the γ -value of Y(Co 1−x Al x ) 2 is nearly constant up to x ∼ = 0.05 and then increases abruptly in the region 0.06 < x < 0.08.…”