Effective spin quantum numbers in iron, cobalt and nickel

Critical magnetic behaviour in one and two dimensions

“…Note that the 57 Fe saturation hyperfine field as well as the magneto-crystalline anisotropy of the 2D iron films show no significant deviations from the bulk values [5,16,17].…”

“…1 our results for the temperature dependence of the spontaneous magnetization of two epitaxial Fe (1 0 0) films grown on silver (1 0 0). It can be seen that the spontaneous magnetization of the Fe film with thickness d ¼ 100 nm is well described by the T 3/2 universal power function of the 2D magnets with halfinteger spin while for the film with d ¼ 200 nm the T 2 universality class of bulk iron [16] is observed. Note that the (non-universal) thickness of the films enters the prefactor of the universal T e functions only.…”

Universal behaviour of the magnetic heat capacity for T→0

“…A qualitatively identical behaviour is observed also for cubic iron and nickel. Note that the spontaneous magnetization of HCP Co obtained using zero field 59 Co NMR measurements decreases according to a T 3/2 power function [14,15]. For cubic iron and nickel the spontaneous magnetization decreases according to a T 2 function [6,16].…”

Shape of Temperature Dependence of Spontaneous Magnetization of Ferromagnets: Quantitative Analysis

“…0 and ! 1, although it has been recently demonstrated [8,9] that an accurate de scription of m in the entire interval 0 < < 1 is provided by a combination of two (in some cases, three) simple power laws, one for each of the temperature subintervals.To advance the matters further, we propose to present the function m in the following form: m 1 ÿ s 3=2 ÿ 1 ÿ s p 1=3 ;(1)where s and p are parameters, p > 3=2, s > 0.Equation (1) is constructed to obey Bloch's 3=2 power law at low temperatures, m 1 ÿ 1 3 s 3=2 as ! 0, whereas in the critical region, !…”