Controlling magnetic clouds in graphene

Jun 12, 2013
Controlling magnetic clouds in graphene

(Phys.org) —Wonder material graphene can be made magnetic and its magnetism switched on and off at the press of a button, opening a new avenue towards electronics with very low energy consumption.

In a report published in Nature Communications, a University of Manchester team led by Dr Irina Grigorieva shows how to create elementary in graphene and then switch them on and off.

This is the first time magnetism itself has been toggled, rather than the magnetization direction being reversed.

Modern society is unimaginable without the use of . They have become an integral part of where devices including hard disks, and sensors employ miniature magnetic components. Each micro-magnet allows a bit of information ('0' or '1') to be stored as two magnetization directions ('north' and 'south'). This area of electronics is called .

Despite huge advances, a big disappointment of spintronics has so far been its inability to deliver active devices, in which switching between the north and south directions is done in a manner similar to that used in modern transistors. This situation may dramatically change due to the latest discovery.

Graphene is a chicken wire made of . It is possible to remove some of these atoms which results in microscopic holes called vacancies. The Manchester scientists have shown that electrons condense around these holes into small electronic clouds, and each of them behaves like a microscopic magnet carrying one unit of magnetism, spin.

Dr Grigorieva and her team have shown that the magnetic clouds can be controllably dissipated and then condensed back.

She explains: "This breakthrough allows us to work towards transistor-like devices in which information is written down by switching graphene between its magnetic and non-magnetic states. These states can be read out either in the conventional manner by pushing an through or, even better, by using a spin flow. Such transistors have been a holy grail of spintronics."

Dr Rahul Nair, who led the experimental effort, comments "Previously, one could only change a direction in which a magnet is magnetized from north to south. Now we can switch on and off the magnetism entirely.

"Graphene already attracts interest in terms of spintronics applications, and I hope that the latest discovery will make it a frontrunner."

Nobel Laureate and co-author of the paper Professor Andre Geim added: "I wonder how many more surprises graphene keeps in store. This one has come out of the blue. We have to wait and see for a few years but the switchable magnetism may lead to an impact exceeding most optimistic expectations."

Professor Antonio Castro Neto, Director of the Research Centre in Singapore and co-author of the report, said: "This work opens the doors for new magnetic devices that are atomically thin and can be easily controlled externally with the application of ordinary electric fields. These new devices can be incorporate in electronic circuits in order to create functionalities for control of magnetism and charge that did not exist before. They unify magnetic memories with electric circuits. It is a true breakthrough."

Explore further: New magnetic graphene may revolutionise electronics

More information: Nair, R. et al. Dual origin of defect magnetism in graphene and its reversible switching by molecular doping, Nature Communications, June 12, 2013. 10.1038/ncomms3010

Related Stories

New spin on graphene

Apr 14, 2011

(PhysOrg.com) -- University of Manchester scientists have found a way to make wonder material graphene magnetic, opening up a new range of opportunities for the world’s thinnest material in the area of ...

New magnetic graphene may revolutionise electronics

May 10, 2013

Researchers from IMDEA-Nanociencia Institute and from Autonoma and Complutense Universities of Madrid (Spain) have managed to give graphene magnetic properties. The breakthrough, published in the journal ...

An electrical switch for magnetism (w/ Video)

May 30, 2013

Researchers at MIT have developed a new way of controlling the motion of magnetic domains—the key technology in magnetic memory systems, such as a computer's hard disk. The new approach requires little ...

Scientists make magnetic new graphene discovery

Apr 14, 2011

(PhysOrg.com) -- University of Maryland researchers have discovered a way to control magnetic properties of graphene that could lead to powerful new applications in magnetic storage and magnetic random access ...

Recommended for you

Making graphene in your kitchen

27 minutes ago

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.

Thinnest feasible nano-membrane produced

Apr 17, 2014

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Wiring up carbon-based electronics

Apr 17, 2014

Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered ...

Making 'bucky-balls' in spin-out's sights

Apr 16, 2014

(Phys.org) —A new Oxford spin-out firm is targeting the difficult challenge of manufacturing fullerenes, known as 'bucky-balls' because of their spherical shape, a type of carbon nanomaterial which, like ...

User comments : 0

More news stories

Easter morning delivery for space station

Space station astronauts got a special Easter treat: a cargo ship full of supplies. The shipment arrived Sunday morning via the SpaceX company's Dragon cargo capsule.