摘要
建立了二维磁性颗粒膜系统的物理模型,应用能量最小原理计算了磁性颗粒的平均磁矩,讨论了系统的铁磁序及反铁磁态(AFM)、铁磁态(FM)和顺磁态(PM)存在的范围和由AFM向FM转变的条件.研究表明:对于磁性颗粒浓度较小(v/a3≈0.05)的纳米级的铁磁颗粒膜系统,其临界温度Tc≈200K.而当在T<Tc且J2l-1=2γ2时,发生由AFM向FM态的相转变;当T>Tc且J2l-1=2γ2T/Tc时,发生FM向PM的相转变;当T=Tc且J2l-1≤2γ2时,发生由AFM态向PM态的转变.这一性质在低温传感器研究领域具有重要的现实意义.
We established a physical model about the two-dimension magnetic granular array system, calculated the average magnetic moment by using energy minimum principle, and discussed the existence scope of ferromagnetic （FM）, antiferromagnetic （AFM） and paramagnetic （PM）, and the transition condition on square lattice particles from AFM to FM. The research shows that the critical temperature is Tc m 200K about nanometer magnetic partic system of low-thickness （ v/a3≈0. 05 ） for the magnetic order change. The system will occur state transition for AFM to FM when T 〈 Tc and j21-1 = 2Y2, and for FM to PM when T 〉 Tc and J2l-1 = 2γ2T/Tc, and for AFM to PM when T = Tc and J2l-1 ≤ 2γ2. These characteristics may be very useful in sensor researching： field at low temperature which needs large changes.
出处
《安徽师范大学学报（自然科学版）》
CAS
北大核心
2013年第1期41-45,共5页
Journal of Anhui Normal University(Natural Science)
基金
重庆市教委科学技术研究项目(KJ061305
KJ081307)
长江师范学院科研项目(077kg41)
关键词
磁性颗粒膜
颗粒磁矩
铁磁
反铁磁态和顺磁态
磁有序
magnetic particle films
particle magnetic moment
ferromagnetic, antiferromagnetic andparamagnetic
magnetic order
