The research field of spintronics (or magneto electronics) has developed into many directions, ranging from fundamental studies to applications. In this talk I will focus on a some elementary and fundamental aspects of spin injection, spin manipulation, and spin transport. The emphasis will be on metallic systems and electrical spin injection and detection. However these elementary concepts are also useful for the understanding of spin injection in semiconductor systems, as well as optical generation and detection of spins.
The talk will consist of the following parts:
4) I will give a brief introduction into mesoscopic transport, highlighting the different transport regimes (classical and quantum transport, diffusive and ballistic transport)
5) A brief overview will be given of the elementary description of spin transport in terms of spin-up and spin-down electrons. Important established magneto-electronic effects such as giant magneto resistance (GMR) and tunneling magnetoresistance (TMR) will be explained.
6) Here I give the elementary description of mesoscopic spin injection, transport, and detection in terms of spin-up and spin-down electrons. Spin relaxation and spin precession will be introduced here.
7) These concepts will be illustrated by recent experiments in my group on spin transport and spin manipulation in 1-dimensional [1] and 0-dimensional systems [2]
8) Future directions will be discussed. In particular I will explain the phenomena of current induced magnetization reversal, where a spin polarized current is used to switch the magnetization direction of a magnetic island.
[1] Electrical detection of spin precession in a metallic mesoscopic spin valve, F.J. Jedema, H.B. Heersche, A.T. Filip, J.J.A. Baselmans, and B.J. van Wees, Nature 416, 713 [2002]
[2] Zero-dimensional spin accumulation and spin dynamics in a mesoscopic island, M. Zaffalon and B.J. van Wees, Phys. Rev. Lett, to be published.