Emerging Nanoelectronic Devices

17Spintronics

Alexander Khitun

Material Science and Engineering, University of California, USA

17.1 Introduction

Spintronics, also known as magnetoelectronics, is an emerging technology exploiting both the intrinsic spin of the electron and its associated magnetic moment, in addition to its fundamental electronic charge, in solid-state devices [1]. Either adding the spin degree of freedom to conventional charge-based electronic devices or using the spin alone has the potential advantages of nonvolatility, increased data processing speed, decreased electric power consumption, and increased integration densities compared with conventional semiconductor devices [2]. Spintronics originates from research on the influence of spin on electrical conduction in ferromagnetic metals by Mott in 1936, Fert and Campbell in 1968, and gained further momentum with the discovery of spin-dependent electron transport phenomena in the 1980s. The notable milestones of Spintronics development include the observation of spin-polarized electron injection from a ferromagnetic metal to a normal metal by Johnson and Silsbee [3], and the discovery of giant magnetoresistance (GMR) independently by Albert Fert et al. [4] and Peter Grünberg et al. [5]. Pioneered by IBM in 1997, the GMR head enabled hard-disk drives to read smaller data bits, which led to a more than 40-fold increase in data storage density over the past seven years [6]. Today, the area of Spintronics is expanding considerably by considering ...