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

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2012,（10）
• 页码范围: 163-166
• 页数: 4页
• 语种: 英文
• DOI: 10.1088/0256-307X/29/10/106301

摘要

The magnetic anomaly associated with the premartensitic transtormation (PT) in Heusler alloy Ni2MnGa 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.