主讲人： 曾浩

时  间： 2011..05.18 下午1：30

地  点： 教三楼321

主  办： 物理系

Abstract

Recent progress in colloidal synthesis has led to magnetic nanoparticles (NP) with tunable size, shape and chemical composition. These NPs show physical properties distinctively different from those of bulk counterparts, which can be harnessed for applications. In this talk, I will discuss the application of magnetic nanoparticles for spintronics. Fe3O4 nanoparticles were self-assembled into an ordered array, which were then integrated into tunnel junction array device structures using photolithography for spin dependent charge transport properties. The theoretically predicted half-metallic properties of magnetite demonstrates sizable magnetoresistance and spin polarization. To realize a diluted magnetic semiconductor (DMS) quantum dot (QD), CdSe QDs are doped with Mn ions A central issue in semiconductor spintronics is the interplay between the carriers and dopants to achieve magnetic order and carrier spin polarization. To this end, DMS QDs serve as a model system to study carrier-dopant exchange interactions. We use both CW and time-resolved, circularly polarized photoluminescence to probe such interactions.