Chapter 1
An Overview of Spintronics
1.1 Introduction
Spintronics, a portmanteau of spin-based electronics, is a new paradigm of electronics
based on spin degree of freedom of the charge carriers. Under the scope of functionality of spintronics, both charge and spin properties of electrons can be utilized
simultaneously. In this direction, production of devices with new functionality is
a fascinating and promising field of research and has potential to revolutionize the
world of electronics. Today, most of the technology are based on electrons and its flow
throughout the devices or circuits. This is the way how electronics devices consisting
of diodes, transistors, FETs, resistors etc. works. Up to this point of time, devices
based on the principle of electronics have been realized by precisely controlling the
charge of the electrons. For a long time, people did not exploit the fact that, apart
from charge, every electron is also having spin, much like the earth precesses around
its axis. On the question of the present day implementation of various microelectronic devices, we never consider the fact that nature has attributed electrons, along
with charge, a spin property. Of course, all well-known ferromagnetic phenomena
are ultimately the mere consequence of the diversified interplay and arrangement
of electron spin. For a long time, in the field of research, spin-dependent electronic
properties of ferromagnetic material and different micromagnetic phenomena have
been supposed as two completely different cases. Although a huge research effort
had been concentrated to elucidate the micromagnetic phenomena, research activities on the spin-dependent electronic properties of ferromagnetic systems were far
less invasive. This is because the application of ferromagnets in industry was mostly
limited so far, based on their bulk magnetization phenomenon only.
Furthermore, from the point of view of information technology, its central theme is
the processing and storing of binary data. In solid-state systems, such operations were
regularly implemented by controlling the charge of carriers, i.e., either of electrons
or holes. Two physically distinguishable states are required to realize classical binary
logic bits, i.e., ‘0’ and ‘1’. In earlier times, in computer memories those two states
were defined by two distinctly different amounts of charge stored in a capacitor.
© Springer Nature Singapore Pte Ltd. 2021
P. Dey and J. N. Roy, Spintronics,
https://doi.org/10.1007/978-981-16-0069-2_1
1
An Overview of Spintronics
1.1 Introduction
Spintronics, a portmanteau of spin-based electronics, is a new paradigm of electronics
based on spin degree of freedom of the charge carriers. Under the scope of functionality of spintronics, both charge and spin properties of electrons can be utilized
simultaneously. In this direction, production of devices with new functionality is
a fascinating and promising field of research and has potential to revolutionize the
world of electronics. Today, most of the technology are based on electrons and its flow
throughout the devices or circuits. This is the way how electronics devices consisting
of diodes, transistors, FETs, resistors etc. works. Up to this point of time, devices
based on the principle of electronics have been realized by precisely controlling the
charge of the electrons. For a long time, people did not exploit the fact that, apart
from charge, every electron is also having spin, much like the earth precesses around
its axis. On the question of the present day implementation of various microelectronic devices, we never consider the fact that nature has attributed electrons, along
with charge, a spin property. Of course, all well-known ferromagnetic phenomena
are ultimately the mere consequence of the diversified interplay and arrangement
of electron spin. For a long time, in the field of research, spin-dependent electronic
properties of ferromagnetic material and different micromagnetic phenomena have
been supposed as two completely different cases. Although a huge research effort
had been concentrated to elucidate the micromagnetic phenomena, research activities on the spin-dependent electronic properties of ferromagnetic systems were far
less invasive. This is because the application of ferromagnets in industry was mostly
limited so far, based on their bulk magnetization phenomenon only.
Furthermore, from the point of view of information technology, its central theme is
the processing and storing of binary data. In solid-state systems, such operations were
regularly implemented by controlling the charge of carriers, i.e., either of electrons
or holes. Two physically distinguishable states are required to realize classical binary
logic bits, i.e., ‘0’ and ‘1’. In earlier times, in computer memories those two states
were defined by two distinctly different amounts of charge stored in a capacitor.
© Springer Nature Singapore Pte Ltd. 2021
P. Dey and J. N. Roy, Spintronics,
https://doi.org/10.1007/978-981-16-0069-2_1
1