Chapter Six - Yttrium Iron Garnet Nano Films: Epitaxial Growth, Spin-Pumping Efficiency, and Pt-Capping-Caused Damping

Abstract

This chapter touches upon several topics related to yttrium iron garnet (YIG)-based spintronics. The chapter consists of four main sections. The first section introduces the structure and magnetic properties of YIG materials. The second section reports on the feasibility of the use of pulsed laser deposition to grow low-damping, nanometer-thick YIG films. Such films are critically needed for both fundamental studies, such as the study of spin pumping, and device applications, such as spin torque oscillators. Surface imperfection-associated damping in YIG nano films is also discussed. The third section presents the determination of efficiency of spin angular momentum transfer across YIG/normal metal interfaces. The last section reports on damping enhancement in YIG nano films due to the magnetic proximity effect in Pt capping layers. The results reported in this section not only demonstrate a new type of damping in magnetic films, but are also of practical significance, as Pt is being widely used for the generation and detection of spin currents.