The exchange interaction effects on magnetic properties of the nanostructured CoPt particles

Abstract

Various manifestations of the exchange interaction effects in magnetization curves of the CoPt nanostructured particles are demonstrated and discussed. The inter-grain exchange constant A in the sponge-like agglomerates of crystallites is estimated as А = (7 ± 1) pJ/m from the approach magnetization to saturation curves that is in good agreement with А = (6.6 ± 0.5) pJ/m obtained from Bloch T 3/2 law. The fractal dimensionality of the exchange coupled crystallite system in the porous media of the disordered CoPt alloy d = (2.60 ± 0.18) was estimated from the approach magnetization to saturation curve. Coercive force decreases with temperature as Hc ~ T 3/2 which is assumed to be a consequence of the magnetic anisotropy energy reduction due to the thermal spin wave excitations in the investigated CoPt particles.

Study of CoxPt1−x nanoalloy formation mechanism via single-source precursors

“…CoPt alloys with near-equiatomic composition have a very high energy of crystallographic magnetic anisotropy ( K 1 ≈ 5 × 10 7 erg cm −3 ) and, as a consequence, high hysteresis properties make them attractive for use as nanomagnets (Komogortsev et al ., 2012; Komogortsev et al ., 2016). Moreover, there are scientific studies in the literature showing the high catalytic activity of this system (Potemkin et al ., 2012; Furukawa et al ., 2016; Potemkin et al ., 2017).…”

Effect of interfacial Dzyaloshinskii-Moriya interaction on polarized neutrons reflection

“…Magnetic and structural parameters of Co/Pt multilayers and neutron beam charachteristics are used for estimations10,39 .…”