The intent of this chapter is to review high frequency magnetic device measurements and modeling work at NIST which is being conducted to support the development of high-speed read sensors, magnetic random access memory, and magnetoelectronic applications (such as isolators and microwaves components). The chapter will concentrate on magnetoresistive devices, those devices whose resistance is a function of the magnetic state of the device, which can in turn be controlled by a magnetic filed. The low-frequency characteristics of magnetoresistive devices will be reviewed. Simulated high-frequency device dynamics, using single-domain and micromagnetic models, will be discussed. Next, high-speed measurements of magnetization rotation and switching in micrometer-size devices will be presented. The effects of thermal fluctuations and disorder on device dynamics will be examined, and high-frequency magnetic noise data will be presented. Finally, the need to understand and control high-frequency magnetic damping will be discussed, and a method for engineering high-frequency magnetization damping using rare-earth doping will be presented.
Citation: Spin Dynamics II
Publisher Info: Spinger Verlag , Heidelberg, GE
Pub Type: Books
magnetodynamics, micromagnetic modeling, GMR, magnetic devices