Spontaneous Magnetization and Magnon-TA Phonon Interaction during the Premartensitic Transformation in Ni2 MnGa Alloy  

作　　者：WAN Jian-Feng 万见峰(School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240)

机构地区：[1]School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240

出　　处：《Chinese Physics Letters》2012年第10期163-166,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(50301011,50571066,51171112);the Scientific Research Foundation for the Returned Overseas Chinese Scholars(State Education Ministry).

摘　　要：The magnetic anomaly associated with the premartensitic transformation(PT)in Heusler alloy Ni_(2)MnGa is investigated by using the Green's function technique based on the magnon-TA phonon interaction.The results of the numerical calculations suggest that the magnetic anomaly during the PT may originate from the strong magnon-TA phonon interaction,because this kind of coupling effect will destroy the magnetic ordering in some local zones and reduce the magnetization of the system.Magnon-magnon interaction plays a positive role in enhancing the magnetization and tends to reduce the PT temperature while this kind of interaction has little effect on the characteristic TA phonon-wavevector corresponding to the anomaly of spontaneous magnetization at the PT temperature.

关 键 词：martensitic ALLOY TRANSFORMATION 

分 类 号：TG1[金属学及工艺—金属学]