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10 Spintronics Applications
non-volatile magnetic random access memories (MRAMs). Recently, STT-MRAMs
have been commercialized as a replacement for SRAMs in embedded cache memories due to their small energy consumption, rapid switching and better endurance.
These have been discussed in subsequent sections.
In the past 10–15 years, the world market has observed a significant development in spintronics-based magnetic sensor technology. GMR, AMR and ordinary
Hall effect-based sensor technologies are steadily being substituted by TMR sensors
owing to their higher output and signal to noise ratio (SNR), good thermal stability,
compatibility with CMOS integration, reduced cost. Main industrial markets today
include:
• The automotive sector [(angular, speed, current, position/proximity sensors), ABS
(antiblocking systems), drive by wire, engine management and ESP (electronic
stabilization program)];
• The full electrification of vehicles and other transportation systems;
• Broader industrial environment industry 4.0 with current and power sensors;
• Linear and angular encoders;
• Scanners, and consumer electronics/smartphones (3D magnetometers/digital
compasses);
• Brand new applications in the IoT,
• Biomedical devices (Spintronics biochip for recognition of proteins, or DNA;
detection of cells/bacteria).
At the same time as, from the semiconductor community, dilute magnetic semiconductors (DMS) have been the subjects of a large number of studies. Spin fieldeffect transistor (spin FET), three-terminal device imagined by Datta and Das, was
presented, which is a foundational concept of a large number of discoveries. Future
ICT needs Gbps data transfer rates via optical fibres. A necessary part of such data
transfer is the high-speed operation of the diode laser, which depends on the efficiency
of the optical isolator. An optical isolator consisting of a DMS is the first practical
use of spintronics based on large magneto-optical effects. Beyond Boolean logic,
spintronics also put forward various potential paths to unconventional computing
schemes. Spintronics is promising for very low power neuromorphic computation.
Spintronics can play a pivotal role in next-generation quantum computation schemes
also.
Length in Magnetic scale
Figure 10.1 represents the classic length scales of magnetic devices and systems.
Transfer of spin polarization takes place through conduction electrons in case of
a conductor. However, in case of insulator, it is done by spin-wave propagation
across local magnetic moments. In bulk magnets, the demagnetizing field from the
edges breaks up the magnetization into domains of different sizes. The domain size
depends on the materials and the domains may range between tens of nanometers
and micrometres or even millimetres. Domain walls separate these domains whose
width results from a trade-off between exchange energy and anisotropy energy. The
width of the domain wall can vary from tens of nanometers to microns. The exchange
10 Spintronics Applications
non-volatile magnetic random access memories (MRAMs). Recently, STT-MRAMs
have been commercialized as a replacement for SRAMs in embedded cache memories due to their small energy consumption, rapid switching and better endurance.
These have been discussed in subsequent sections.
In the past 10–15 years, the world market has observed a significant development in spintronics-based magnetic sensor technology. GMR, AMR and ordinary
Hall effect-based sensor technologies are steadily being substituted by TMR sensors
owing to their higher output and signal to noise ratio (SNR), good thermal stability,
compatibility with CMOS integration, reduced cost. Main industrial markets today
include:
• The automotive sector [(angular, speed, current, position/proximity sensors), ABS
(antiblocking systems), drive by wire, engine management and ESP (electronic
stabilization program)];
• The full electrification of vehicles and other transportation systems;
• Broader industrial environment industry 4.0 with current and power sensors;
• Linear and angular encoders;
• Scanners, and consumer electronics/smartphones (3D magnetometers/digital
compasses);
• Brand new applications in the IoT,
• Biomedical devices (Spintronics biochip for recognition of proteins, or DNA;
detection of cells/bacteria).
At the same time as, from the semiconductor community, dilute magnetic semiconductors (DMS) have been the subjects of a large number of studies. Spin fieldeffect transistor (spin FET), three-terminal device imagined by Datta and Das, was
presented, which is a foundational concept of a large number of discoveries. Future
ICT needs Gbps data transfer rates via optical fibres. A necessary part of such data
transfer is the high-speed operation of the diode laser, which depends on the efficiency
of the optical isolator. An optical isolator consisting of a DMS is the first practical
use of spintronics based on large magneto-optical effects. Beyond Boolean logic,
spintronics also put forward various potential paths to unconventional computing
schemes. Spintronics is promising for very low power neuromorphic computation.
Spintronics can play a pivotal role in next-generation quantum computation schemes
also.
Length in Magnetic scale
Figure 10.1 represents the classic length scales of magnetic devices and systems.
Transfer of spin polarization takes place through conduction electrons in case of
a conductor. However, in case of insulator, it is done by spin-wave propagation
across local magnetic moments. In bulk magnets, the demagnetizing field from the
edges breaks up the magnetization into domains of different sizes. The domain size
depends on the materials and the domains may range between tens of nanometers
and micrometres or even millimetres. Domain walls separate these domains whose
width results from a trade-off between exchange energy and anisotropy energy. The
width of the domain wall can vary from tens of nanometers to microns. The exchange