Spin Dynamics in Invar (Fe_<65>Ni_<35>, Fe_3Pt) and Non Invar (Fe_<50>Ni_<50>) Alloys

概要

論文の詳細を見る
Sr>in dvnamics of a disordered Invar allov FessNiss, an ordered Invar alloyFeePt as well as a non Invar disordered allot' FesoNiso have been studied byneutron scatterins. It has been found that both Invar allo>rs show commonanomalous d>'namical r>ror>erties. Well defined masnon gI0UpS could be detectedup to the Curie temperature. The spin wave stiffness constant D(T) varies withtemperature as D(7')=D.(1 -CT""). The magnon excitations, however, couldext>lain only' about a half of the temrerature variation of magnetization MAT)for the Invar alloys, in spite of the fact that the integrated intensity measurementsof the magnon spectra suggest that no other excitations take part in M(T). MAT)of non Invar alloy could be accounted for by the magnon excitations. The magnonsin the Invar allays dampen significantly with increasing temperature as wasapparent in the linewidth T (q, T) obeying a relation T(q, T)=(T.-FaT')q' withcx<1, quite different from the Heiseuaberg system.
社団法人日本物理学会の論文
1981-05-15