Micromagnetics of Nano-structures

点击翻译按钮获取中文摘要

Small magnetic structures are being developed formagnetic sensors (for example, exploiting thegiant magnetoresistance effect, or tunneling magnetoresistance)for nonvolatile memories exploiting either the Hall effect or magnetotransporteffects and for storage on a nano scale.They present challenges in design for controllingthe value and reproducibility of the switching field.Temperature effects as well as fluctuationof the grain structure on a mesoscopic scale become important.At the moment, magnetic nonvolatile memories are being developed byIBM-Siemans (Infinion) and the Motorola Companies.The uniformity of the switching field is a major stumbling block in thecommercilaiztaion of high density nonvolatile magnetic memories.At the moment the yield of addressable sites is very small.Nearly all current micromagnetics calculations are carried outat zero temperature and do not include the temperature effects.In addition, very few systematic investigation were carried out.We propose to study and develop a way to predict the devicecharacteristics and enable their optimum designwith techniques that we have developed over the last several years.These include (a) calculations from an analytic point of view incombination with a finite temperature Monte Carlo code that we have written andoptimized; (b) experimental studies of the switching fieldcharacteristics of our in-house e-beam patterned submicronstructures.