Graphene - Page 9

Researchers from the University of California, Riverside successfully achieved tunneling-spin-injection into Graphene. The researchers inserted a nanometer-thick insulating layer, known as a tunnel barrier in between the ferromagnetic electrode and the graphene layer. They found that the spin injection efficiency increased dramatically. A 30-fold increase, actually.

The team also made an unexpected discovery that explains short spin lifetimes of electrons in graphene that have been reported by other experimental researchers. People usually assume that the Hanle measurement accurately measures the spin lifetime, but this result shows that it severely underestimates the spin lifetime when the ferromagnet is touching the graphene, said Wei Han, the first author of the research paper and a graduate student. This is good news because it means the true spin lifetime in graphene must be longer than reported previously potentially a lot longer.

Osaka's university has a Spintronics research group that is working towards MRAM and STT-RAM using several materials including Graphene. Here's a nice intro video about the group:

QuantumWise A/S is announcing a new release of its software package for atomic-scale simulations of nanoscale electronic and spintronic devices, Atomistix ToolKit (ATK). This code is able to compute electronic structure and transport properties (e.g. I-V characteristics) of nanoscale structures such as nanotubes, graphene, molecular electronics devices, magnetic tunnel junctions and other magnetic system, interface structures, nanowires, etc.

Based on semi-empirical methods, the newly released package extends the company's modeling platform, which already comprises a density-functional theory (DFT) method, to allow faster simulations of larger structures (>1,000 atoms). The new model also offers a better description of semiconducting materials.

Moreover, a new electrostatic model is introduced, which supports inclusion of an arbitrary configuration of dielectric and metallic regions. These gates are described fully self-consistently electrostatically, and this allows for a realistic multi-scale simulation of nanoscale transistor structures.

The QuantumWise platform is based on an open architecture which integrates a Python-based scripting language, NanoLanguage, with a graphical user interface, Virtual NanoLab. The new release extends this platform by including support also for GPAW, an external grid-based DFT code specifically designed for applications within catalysis and surface science.

We're happy to announce a new addition to the Metalgrass site network: Graphene-Info. Graphene is a sheet, one-atom-thick of carbon atom, in a honeycomb crystal lattice. If you use many layers of graphene, stacked one on top of the other, you’ll get Graphite. Graphene has many uses - Spintronics, sensors, ICs (for example a transparent backplane for OLEDs), ultra-capacitors and more.

We hope you'll enjoy the new site...

A material just six atoms thick in which electrons appear to be guided by conflicting laws of physics depending on their direction of travel has been discovered by a team of physicists at the University of California, Davis. Working with computational models, the team has found that the electrons in a thin layer of vanadium dioxide sandwiched between insulating sheets of titanium dioxide exhibit one set of properties when moving in forward-backward directions, and another set when moving left to right.

With its unique properties, the material could open up a new world of possibilities in the emerging field of spintronics technology, which takes advantage of the magnetic as well as the electric properties of electrons in the design of novel electronic devices.

Graphene is a nanomaterial combining very simple atomic structure with intriguingly complex and largely unexplored physics. Since its first isolation about four years ago researchers suggested a large number of applications for this material in anticipation of future technological revolutions. In particular, graphene is considered as a potential candidate for replacing silicon in future electronic devices.

Theoretical physicists from the Swiss Federal Institute of Technology in Lausanne (EPFL) and Radboud University of Nijmegen (The Netherlands) performed a virtual crash-test of graphene as a material for future spintronic devices, possible components of future computers. The material successfully passed the test, although, with some reservations.

A small ribbon made of the carbon honeycomb pattern found in graphite and nanotubes could display intriguing electronic properties and serve as a material for spin-based electronics (spintronics), researchers have predicted.

Steven Louie's group at the University of California at Berkeley, US, has now used ab initio calculations to show that ceratain carbon nanoribbons will display half-metallicity. The researchers calculated the electronic properties of graphene sheets (the single layers of hexagonally arranged carbon atoms found in graphite). Specifically, they looked at ribbons between 1.5 and 6.7 nm wide,  with a zigzag border at each side (see image below).