Graphene - Page 5

Researchers develop graphene-based room-temperature spin field-effect transistor

Researchers from Chalmers University developed a new graphene-based room-temperature spin field-effect transistor (G-FET).

Graphene spintronics FETs image

As part of the research, it was demonstrated that the spin characteristics of graphene can be electrically regulated in a controlled way, even at an ambient temperature. This structure is not only useful to make spin-logic devices - it can also be used to integrate device-level magnetic memory (MRAM) elements.

Read the full story Posted: Jul 09,2017

Researchers use graphene and CNTs to design an all-carbon spin logic gate

Researchers from the University of Texas in Dallas developed an all-carbon spin logic design for a switch that could be the basis of carbon spin logic devices.

The design is based on graphene nanoribbons and carbon nanotubes, which in conjunction can be used to create cascaded logic gates that are not physically linked. The communication between the gates happens via an electromagnetic wave (and does not use any physical movement of electrons), it is anticipated that communication will be much quicker - with the potential for terahertz clock speeds. The size of these logic gates will be much smaller than silicon based gates.

Read the full story Posted: Jun 08,2017

Electron spin can be used to reduce contact resistance in graphene electronics

Researchers from the NUS discovered that manipulating the electron spin lowers the contact resistance in graphene electronics.

Spin filtering in metal-graphene interfaces image

Graphene is an excellent conductor, but metal-graphene interfaces suffer from large electrical resistance. The researchers have shown that edga-contacted device geometries in metallic-graphene interfaces feature some of the lowest contact resistances reported to date - significantly lower than in surface-contracted interfaces. The researchers explain that this is due to the different behavior of electron spins in these geometries.

Read the full story Posted: May 22,2017

NRL researchers produce spin-filtering at room temperature

Researchers from the US Naval Research Laboratory (NRL) demonstrated metallic spin filtering at room temperatures, using a ferromagnet-graphene-ferromagnet thin film junction device.

Spin filtering graphene junction (NRL)

Spin filtering has been theoretically predicted, and previously seen only for high-resistance structures at cryogenic temperatures. This is the first time that someone demonstrated the effect in room temperatures, and with very low resistance in arrays of multiple devices.

Read the full story Posted: Dec 22,2016

A lateral electric field can control the spin polarization in zigzag graphene ribbons

Researchers from Grennole Alpes University in France have demonstrated using atomistic calculations that a lateral electric field can be used to tune the carrier mobility and change the spin polarization of the current driving through zigzag graphene ribbons. The researchers say that these effects can be nicely exploited in spintronics devices.

Spin polarization in ZGNR image

The calculations predict a high variation of the carrier mobility, mean free path and spin polarization in the ZGNRs. It turns out that configurations with almost 100% spin-polarized current can be switched on and off.

Read the full story Posted: Nov 16,2016

The EU's graphene flagship project kickstarts graphene spintronics research

The Graphene Flagship, the $1 billion EU graphene research initiative, includes a Spintronics Work Package - the aims to explore graphene's role in spintronics.

There are currently five projects in the spintronics field under the flagship:
  • HiMagGraphene: Atomic-scale control of graphene magnetism using hydrogen atoms
  • iSpinText: Induced Spin Textures in van der Waals Heterostructures
  • SOgraph: Tailoring Spin-Orbit effects in Graphene for spin-orbitronic applications
  • TAILSPIN: Tailoring spin-interactions in graphene nanoribbons for ballistic fully spin-polarized devices
  • Trans2DTMD: Theoretical investigation of electronic transport in functionalized 2D transition metal dichalcogenides

Read the full story Posted: Jun 06,2016

Perfect zigzag-edged graphene ribbons highly attractive for Spintronics applications?

Researchers have succeeded, for the first time, in producing graphene nanoribbons (GNRs) with perfect zigzag edges. Electrons on these zigzag edges exhibit different (and coupled) rotational spin - which means they could be highly attractive for next-gen Spintronics devices.

GNRs with eprfect zigzag edges image

In their work, the research team describes how it managed to synthesize GNRs with perfectly zigzagged edges using suitable carbon precursor molecules and a perfected manufacturing process. The zigzags followed a very specific geometry along the longitudinal axis of the ribbons.

Read the full story Posted: Mar 30,2016

Graphene coated cobalt to greatly benefit spintronic devices

Researchers from France's Joseph Fourier University discovered that coating a cobalt film in graphene could double the film's perpendicular magnetic anisotropy (PMA), so that it reaches a value 20 times higher than that of traditional metallic cobalt/platinum multilayers.

Graphene coated cobalt to greatly benefit spintronic devices image

High-PMA materials are being researched for their applications in next-generation spintronic devices.

Read the full story Posted: Dec 23,2015

New room-temperature tunnel device developed using graphene as tunnel barrier and transport channel

Researchers from the U.S. Naval Research Laboratory (NRL) developed a new type of room-temperature tunnel device structure in which the tunnel barrier and transport channel are both made of graphene.

NRL scientists use graphene as tunnel barrier for spintronics image

In this new design, hydrogenated graphene acts as a tunnel barrier on another layer of graphene for charge and spin transport. The researchers demonstrated spin-polarized tunnel injection through the hydrogenated graphene, and lateral transport, precession and electrical detection of pure spin current in the graphene channel. The team sasy that the spin polarization values are higher than those found using more common oxide tunnel barriers, and spin transport at room temperature.

Read the full story Posted: Jul 17,2015

EU's Graphene Flagship is looking for a partner company for spintronics research

The Graphene Flagship announced a €350,000 work package that explores the potential of graphene spintronics for future devices and applications. The GF is searching for a new partner company to support device development and commercialisation of graphene spintronics, by applying it in specific device architectures dedicated to commercially viable applications and determining the required figures of merits.

The project's budget is for the period 1 April 2016 – 31 March 2018, and includes devices which require optimized (long distance) spin transport, spin-based sensors, and new integrated two-dimensional spin valve architectures. The Graphene Flagship expects that at the start of the Horizon 2020 phase (April 2016), spin injection and spin transport in graphene and related materials will have been characterised and the resulting functional properties will have been understood and modeled.

Read the full story Posted: Jan 28,2015