Spintronics (a portmanteau meaning spin transport electronics, also known as spin-electronics or Flextronics, 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. Spintronics differs from the older magnetoelectronics, in that the spins are not only manipulated by magnetic fields, but also by electrical fields.
In order to develop spintronics technology, it is first necessary to fully explore potential materials and their properties; by obtaining a thorough understanding of spintronic phenomena we can effective utilize them to create spin-engineered materials and working devices. Spintronics is an emerging field of nanoscale electronics involving the detection and manipulation of electron spin.
Today microelectronic devices are based on controlling the charge of electrons, either by storing it or sending it flowing as current. However, electrical current is actually composed of two types of electrons, spin-up and spin-down electrons, which form two largely independent spin currents. In the past 15 years, there has been a revolution in our understanding of generating, manipulating and detecting spin-polarized electrical current which makes possible entirely new classes of spin-based sensor, memory and logic devices. This new field of science and technology is now commonly referred to as spintronics.
History
Spintronics emerged from discoveries in the 1980s concerning spin-dependent electron transport phenomena in solid-state devices. This includes the observation of spin-polarized electron injection from a ferromagnetic metal to a normal metal by Johnson and Silsbee (1985) and the discovery of giant magnetoresistance independently by Albert Fert et al. The origins of spintronics can be traced back even further to the ferromagnet/superconductor tunneling experiments pioneered by Meservey and Tedrow, and initial experiments on magnetic tunnel junctions by Julliere in the 1970s. The use of semiconductors for spintronics can be traced back at least as far as the theoretical proposal of a spin field-effect-transistor by Datta and Das in 1990.
A particularly important class of spintronic materials are nano-engineered magnetic heterostructures (or multilayers) whose critical element is a sandwich of two ultra-thin magnetic layers separated by atomically thin non-magnetic conducting or insulating layers, forming what are called spin-valve or magnetic tunnel junction devices. Such sandwiches can exhibit giant changes in conductance when the magnetic orientation of the magnetic layers is changed. Spin-valve sensors were pioneered by Stuart Parkin at the Almaden Research Center in 1989-1991 and today are a key component of all magnetic hard-disk drives, which enabled their nearly 1,000-fold increase in capacity over the past 8 years. This means that today all information in the world can be stored in digital form and accessed remotely, effectively from any part of the world: the consequences have been enormous and one can truly make the case that spintronics has made possible today digital world.
At Almaden, we study a wide range of spintronic materials and devices both to discover new physical phenomena and for applications in novel sensor, memory and logic technologies.
In order to develop spintronics technology, it is first necessary to fully explore potential materials and their properties; by obtaining a thorough understanding of spintronic phenomena we can effective utilize them to create spin-engineered materials and working devices. Spintronics is an emerging field of nanoscale electronics involving the detection and manipulation of electron spin.
Today microelectronic devices are based on controlling the charge of electrons, either by storing it or sending it flowing as current. However, electrical current is actually composed of two types of electrons, spin-up and spin-down electrons, which form two largely independent spin currents. In the past 15 years, there has been a revolution in our understanding of generating, manipulating and detecting spin-polarized electrical current which makes possible entirely new classes of spin-based sensor, memory and logic devices. This new field of science and technology is now commonly referred to as spintronics.
History
Spintronics emerged from discoveries in the 1980s concerning spin-dependent electron transport phenomena in solid-state devices. This includes the observation of spin-polarized electron injection from a ferromagnetic metal to a normal metal by Johnson and Silsbee (1985) and the discovery of giant magnetoresistance independently by Albert Fert et al. The origins of spintronics can be traced back even further to the ferromagnet/superconductor tunneling experiments pioneered by Meservey and Tedrow, and initial experiments on magnetic tunnel junctions by Julliere in the 1970s. The use of semiconductors for spintronics can be traced back at least as far as the theoretical proposal of a spin field-effect-transistor by Datta and Das in 1990.
A particularly important class of spintronic materials are nano-engineered magnetic heterostructures (or multilayers) whose critical element is a sandwich of two ultra-thin magnetic layers separated by atomically thin non-magnetic conducting or insulating layers, forming what are called spin-valve or magnetic tunnel junction devices. Such sandwiches can exhibit giant changes in conductance when the magnetic orientation of the magnetic layers is changed. Spin-valve sensors were pioneered by Stuart Parkin at the Almaden Research Center in 1989-1991 and today are a key component of all magnetic hard-disk drives, which enabled their nearly 1,000-fold increase in capacity over the past 8 years. This means that today all information in the world can be stored in digital form and accessed remotely, effectively from any part of the world: the consequences have been enormous and one can truly make the case that spintronics has made possible today digital world.
At Almaden, we study a wide range of spintronic materials and devices both to discover new physical phenomena and for applications in novel sensor, memory and logic technologies.
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