September 2013

Researchers from the University of Utah (the same professor whose "Spin Effects in Organic Optoelectronic Devices" talk we just posted on) developed a new platinum-doped polymer that can be used to create light emitting devices, efficient OLEDs and OPVs and perhaps even Spintronics-based memory devices.

The basic idea is to take an organic polymer and insert (dope) platinum atoms at different intervals. Different intervals result in different light colors - including white. So the same molecule can emit different colored light at the same time and thus achieve white light. The researchers created two versions of the same polymer. The Pt-1, which emits violet and yellow light as it has a platinum atom in every unit or link. The Pt-3 has a platinum atom every third unit and it emits blue and orange light. We do not have more information regarding how these materials can be used as Spintronics devices.

Professor Z. Valy Vardeny from the University of Utah talks about several important developments in the field of organic spintronics and magnetic field effect in organic optoelectronic devices.

Vardeny talks about a spin-OLED that they developed in 2012 using using two FM injecting electrodes, where the electroluminescence depends on the mutual orientation of the electrode magnetization directions. This development has opened up research studies into organic spin-valves in the space-charge limited current regime.

Researchers from Korea's RIKEN Center proposed a device that instead of moving electrons is able to transport information using electron spin over long distances. The idea is to sandwich two adjacent thin magnetic films between superconducting layers.

The researchers explain that in conventional superconductors, the electrons are bound together in pairs formed by antiparallel electron spins (this is called a spin-singlet Cooper pair). However, with a ferromagnetic layer nearby, the spin of the two electrons in such a Cooper pair will align itself in the same direction as the magnetic field. So you can move the spin-triplter Cooper pairs from the superconductor into the ferromagnetic layer, where they are very stable and long-lived. The researchers have shown mathematically that within the ferromagnetic layer, those pairs are able to carry spin currents over extended distances of several tens to hundreds of nanometers, and possibly even more (depends on the purity of the magnetic material). In this movement, no hear will be generated.

Researcher from North Carolina State University developed a new material, strontium tin oxide (Sr3SnO) that is a dilute magnetic semiconductors and can be integrated into silicon chips. This means it may be useful for room-temperature Spintronics devices.

The researchers created this material as an epitaxial (single crystal) thin film on a silicon chip. They actually wanted to test whether it is a topological insulator, but surprisingly found out that it has magnetic semiconductor.

Researchers from the University of Nottingham are studying a new antiferromagnetic spintronic material - tetragonal CuMnAs. They say that this new material enables new device structure designs that combine Spintronic and nanoelectronic functionality - at room temperature.

An antiferromagnet is a material in which electron spin on adjacent atoms cancel each other out - and so it was considered unsuitable for Spintronics applications. However it was recently discovered that these materials have a physical phenomena that can enable memory and sensing applications.