Affiliation:
1. Infosys Limited, Pune, Maharashtra, India
2. Tata Consultancy Services, Chennai, Tamilnadu, India
Abstract
We already know that electrons have a charge along with a spin, but until recently, these two have been considered separately. The motion of electric charge is considered as the heart of electronic circuits, and the flow of electron spin plays a crucial role in spintronic circuits. Adding the spin degree of freedom provides new capabilities, new effects, and new functionalities. It all started with the discovery of the Giant Magnetoresistance (GMR) in 1988, which opened the road to an effective control of the motion of the electron charges by focusing on their spin through the orientation of magnetization. Today, spintronics has entered into almost every household as the read sensors for the hard drives present in every desktop and most laptops. Magnetic Random Access Memory (MRAM) and Spin Transfer Torque (STT) RAM are replacing Static RAM where ultra-dense memories are not required. Soon these spintronic memories will penetrate the cell phone market because they offer lower power and are non-volatile. The potential held by Spintronics is very promising for new advancements in science and technology in the 21st century. This paper discusses the evolution of spintronics from the initial research of spin-dependent transport in ferromagnetic materials to the discovery of the giant magnetoresistance and to the most recent advances. Today, this field of research is extending considerably, with very encouraging new technologies like the phenomena of spin transfer, molecular spintronics, nanoscale spintronics, and single-electron spintronics.