The Use of Magnetic Spectroscopy in the Investigation of the Magnetic Viscosity of Nanoparticles at Microwave Frequencies

摘要：

　　In the case of uniaxial single domain superparamagnetic particles,the magnetic moment,m,may switch between two anti-parallel equilibrium positions,however,the switching does not happen instantaneously and parameters which influence this action in the particles are the magnetic viscosity,ηm,the interwell and intrawell relaxation times,ΤN and Τ0.Here,by measurement of the field and frequency dependence of the complex magnetic susceptibility,χ(ω)= χ′(ω)-iχ″(ω),these values are determined for two colloidal suspensions of manganese ferrite in isopar-m of approximately the same particle size and magnetisation but differing stoichiometry,x,with a view to determining,what effect,if any,the value of x has on ηm and hence the switching time of the magnetic moment.

作者: P.C.Fannin C.N.Marin

作者单位: Department of Electronic and Electrical Engineering,Trinity College,Dublin 2,Ireland Faculty of Physics,West University of Timisoara,Bd.V.Parvan no.2,Timisoara,Romania

会议类型: 国际会议

会议名称: Progress in Electromagnetics Research Symposium 2011(2011年电磁学研究新进展学术研讨会)

会议地点: 苏州

会议语种:英文

页码: 114-117

在线出版日期: 2011-09-01（万方平台首次上网日期，不代表论文的发表时间）