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.

Today's 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 spintronics¹.

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's 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.

1. S. S. P. Parkin et al., Proc. IEEE 91, 661 (2003).

• Oxides
  • LSMO
  • STO
  • SRO
  • Magnetite
  • NiO/CoO/MnO
  • MgO
• Soft Magnetic Materials
• Magnetic Tunnel Junctions -- material aspects
  • Giant tunneling spin polarization
  • Kondo assisted tunneling
  • IETS
• Carbon-based Materials

Spintronics Materials and Phenomena

Oxides Soft magnetic Materials Magnetic Tunnel Junctions Carbon-based Materials