Magnetization of Permalloy at Low Temperatures
- 1 March 1964
- journal article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 35 (3) , 802-803
- https://doi.org/10.1063/1.1713480
Abstract
Pyromagnetic measurements of the magnetization of a single-crystal sphere of Permalloy (79.65 Ni-20.35 Fe by weight) in the range 4.2°–100°K and with applied fields of 4, 9, and 14 kOe parallel to the [111] crystal axis are reported and interpreted in terms of spin-wave theory. The spin-wave energy gap obeys the theoretical expression in terms of internal applied field, magnetocrystalline anisotropy field (negligible), and average spin-wave demagnetizing field. The coefficients appropriate to zero gap are C = (7.6±0.1)×10−6 deg−3/2 for the T3/2 term and D/C≤±0.2×10−3 deg−1 for the T5/2 term. The analysis of the data is made using a new graphical method which displays visually the quality of fit to the theory. The C value implies (JS)eff/kB=134°K in good agreement with independent determinations of the spin-wave dispersion parameter.This publication has 3 references indexed in Scilit:
- Deviations fromLaw for Magnetization of Ferrometals: Ni, Fe, and Fe+3% SiPhysical Review B, 1963
- Pyromagnetic Test of Spin Wave Theory in Metallic NickelJournal of Applied Physics, 1962
- Experimental g′ and g Values of Fe, Co, Ni, and Their AlloysJournal of Applied Physics, 1961