Graphene and 'spintronics' combo looks promising

Jan 25, 2011

A team of physicists has taken a big step toward the development of useful graphene spintronic devices. The physicists, from the City University of Hong Kong and the University of Science and Technology of China, present their findings in the American Institute of Physics' Applied Physics Letters.

Graphene, a two-dimensional crystalline form of carbon, is being touted as a sort of "Holy Grail" of materials. It boasts properties such as a breaking strength 200 times greater than steel and, of great interest to the semiconductor and industries, that can blaze through it 100 times faster than in silicon.

Spintronic devices are being hotly pursued because they promise to be smaller, more versatile, and much faster than today's electronics. "Spin" is a quantum mechanical property that arises when a particle's intrinsic rotational momentum creates a tiny magnetic field. And spin has a direction, either "up" or "down." The direction can encode data in the 0s and 1s of the binary system, with the key here being that spin-based data storage doesn't disappear when the electric current stops.

"There is strong research interest in spintronic devices that process information using electron spins, because these novel devices offer better performance than traditional and will likely replace them one day," says Kwok Sum Chan, professor of physics at the City University of Hong Kong " is an important material for spintronic devices because its can maintain its direction for a long time and, as a result, information stored isn't easily lost."

It is, however, difficult to generate a spin current in graphene, which would be a key part of carrying information in a graphene spintronic device. Chan and colleagues came up with a method to do just that. It involves using spin splitting in monolayer graphene generated by ferromagnetic proximity effect and adiabatic (a process that is slow compared to the speed of the electrons in the device) quantum pumping. They can control the degree of polarization of the spin current by varying the Fermi energy (the level in the distribution of electron energies in a solid at which a quantum state is equally likely to be occupied or empty), which they say is very important for meeting various application requirements.

Explore further: Protons fuel graphene prospects

More information: The article, "Spin current generation by adiabatic pumping in monolayer graphene," by Qingtian Zhang, K. S. Chan, and Zijing Lin appears in the journal Applied Physics Letters. See: link.aip.org/link/applab/v98/i3/p032106/s1

Provided by American Institute of Physics

5 /5 (2 votes)

Related Stories

Armchair nanoribbons made into spintronic device

Jan 25, 2011

In a development that may revolutionize handheld electronics, flat-panel displays, touch panels, electronic ink, and solar cells, as well as drastically reduce their manufacturing costs, physicists in Iran have created a ...

Physicists put a new spin on electrons

Apr 15, 2009

In the first demonstration of its kind, researchers at the University of British Columbia have controlled the spin of electrons using a ballistic technique--bouncing electrons through a microscopic channel of precisely constructed, ...

Spin-polarized electrons on demand

Jan 21, 2009

Many hopes are pinned on spintronics. In the future it could replace electronics, which in the race to produce increasingly rapid computer components, must at sometime reach its limits. Different from electronics, where whole ...

Spin-polarized electrons on demand

Jan 15, 2009

Many hopes are pinned on spintronics. In the future it could replace electronics, which in the race to produce increasingly rapid computer components, must at sometime reach its limits. Different from electronics, where whole ...

Spintronic transistor is developed

Oct 23, 2005

Researcher Christian Schoenenberger and colleagues at the University of Basel, Switzerland, developed a carbon nanotube transistor, opening a promising avenue toward the introduction of spin-based devices into computer chips, ...

Recommended for you

Protons fuel graphene prospects

5 hours ago

Graphene, impermeable to all gases and liquids, can easily allow protons to pass through it, University of Manchester researchers have found.

Cooling with the coldest matter in the world

Nov 24, 2014

Physicists at the University of Basel have developed a new cooling technique for mechanical quantum systems. Using an ultracold atomic gas, the vibrations of a membrane were cooled down to less than 1 degree ...

Magnetic fields and lasers elicit graphene secret

Nov 24, 2014

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) have studied the dynamics of electrons from the "wonder material" graphene in a magnetic field for the first time. This led to the discovery of ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.