Speaker
Dr
khashayar khazen
(Condensed matter national lab- IPM)
Description
Application of synchrotron-based magnetic characterization techniques has opened new insights into the physics of the magnetic structures and devices in condensed matter and has largely contributed to the development of novel magnetic materials in the relevant fields of science and technology such as spintronics. A well-known example of such techniques is the XMCD spectroscopy, which has so far played a major role in the investigation of the magnetic properties of single and multi-component systems where element, magnetic phase and thickness dependencies of the investigated magnetic structures and their magnetic couplings are concerned.
In this regard, the principles of the XMCD technique and its applications will be briefly presented within the frame of a case study, where the interlayer magnetic couplings of GaMnAs ferromagnetic semiconductor and a metallic ferromagnet has been studied using this technique. Since the dawn of spintronics, ferromagnetic semiconductors have attracted huge attention because of the co-existence of both semiconducting and magnetic characteristics. This feature provides the possibility of controlling both charge and spin degrees of freedom of the information carriers which can be used to store and process them in unified devices such as spinFETs, Racetrack memories, and magnetic tunnel junctions and hence has made them promising systems for spintronic and more recently for valleytronic applications. Their main problem, however, is their low curie temperature which prohibits their direct application. Among numerous proposed approached to increase the curie temperature, the interlayer magnetic coupling with a high Tc ferromagnet such as Fe layer was first proposed by Macherozzi et al. It was proposed that the interfacial region inside GaMnAs layer would retain its ferromagnetic phase up to room temperature via this approach.
Author
Dr
khashayar khazen
(Condensed matter national lab- IPM)
