Putting a new spin on current research

November 15, 2008
QuantumSpin

Enlarge

Microwaves are used to control the spin state of electrons held in silicon. This spin state can be watched in real time by measuring the electric current flowing between the (gray) electrodes. Credit: UCL/London Centre for Nanotechnology

Physicists in the USA and at the London Centre for Nanotechnology have found a way to extend the quantum lifetime of electrons by more than 5,000 per cent, as reported in this week's Physical Review Letters. Electrons exhibit a property called 'spin' and work like tiny magnets which can point up, down or a quantum superposition of both. The state of the spin can be used to store information and so by extending their life the research provides a significant step towards building a usable quantum computer.

"Silicon has dominated the computing industry for decades," says Dr Gavin Morley, lead author of the paper. "The most sensitive way to see the quantum behaviour of electrons held in silicon chips uses electrical currents. Unfortunately, the problem has always been that these currents damage the quantum features under study, degrading their usefulness."

Marshall Stoneham, Professor of Physics at UCL (University College London), commented: "Getting the answer from a quantum computation isn't easy. This new work takes us closer to solving the problem by showing how we might read out the state of electron spins in a silicon-based quantum computer."

To achieve the record quantum lifetime the team used a magnetic field twenty-five times stronger than those used in previous experiments. This powerful field also provided an additional advantage in the quest for practical quantum computing: it put the electron spins into a convenient starting state by aligning them all in one direction.

For more information, see the paper published in Physical Review Letters, November 14 2008, by G. W. Morley (London Center for Nanotechnology), D. R. McCamey (University of Utah), H. A. Seipel (University of Utah), L.-C. Brunel (National High Magnetic field Laboratory), J. van Tol (National High Magnetic field Laboratory) and C. Boehme (University of Utah). (http://link.aps.or … /v78/e045303)

Source: University College London

4.7 /5 (14 votes)  

Rank 4.7 /5 (14 votes)
Related Stories
Relevant PhysicsForums posts
  • Simple Torque from Gravity Problem
    created2 hours ago
  • Books To Inspire a Beginnig Physics Student
    created4 hours ago
  • Pith balls problem
    created5 hours ago
  • Electrostatics
    created5 hours ago
  • what is phase constant
    created5 hours ago
  • Basics In electromagnetic wave
    created5 hours ago
  • More from Physics Forums - General Physics

More news stories

Putting the squeeze on planets outside our solar system

(PhysOrg.com) -- Using high-powered lasers, scientists at Lawrence Livermore National Laboratory and collaborators discovered that molten magnesium silicate undergoes a phase change in the liquid state, abruptly ...

Physics / Condensed Matter

created 16 hours ago | popularity 4.3 / 5 (7) | comments 0 | with audio podcast

Hovering not hard if you're top-heavy, researchers find

Top-heavy structures are more likely to maintain their balance while hovering in the air than are those that bear a lower center of gravity, researchers at New York University's Courant Institute of Mathematical Sciences ...

Physics / General Physics

created 17 hours ago | popularity 5 / 5 (2) | comments 1 | with audio podcast

Borexino Collaboration succeeds in spotting pep neutrinos emitted from the sun

(PhysOrg.com) -- To learn more about how the sun works, scientists study particles that are emitted from it into space due to thermonuclear reactions that occur inside; by applying known physics principles, ...

Physics / General Physics

created Feb 09, 2012 | popularity 4.6 / 5 (7) | comments 0 | with audio podcast report

Transparent iron? For the first time, an experiment shows that atomic nuclei can become transparent

At the high-brilliance synchrotron light source PETRA III, a team of DESY scientists headed by Dr. Ralf Röhlsberger has succeeded in making atomic nuclei transparent with the help of X-ray light. At the ...

Physics / General Physics

created Feb 08, 2012 | popularity 4.8 / 5 (11) | comments 3 | with audio podcast

SLAC, Stanford team focuses on high-energy electrons to treat cancer

Accelerator physicists at SLAC and cancer specialists from Stanford are working on a new technology that could dramatically reduce the time needed for cancer radiation treatments. The team ran an initial experiment ...

Physics / General Physics

created 20 hours ago | popularity 5 / 5 (2) | comments 0


Google users warned of threat to smartphone wallets

Users of Google smartphone wallets were being warned on Friday that there is a way to crack pass codes intended to thwart thieves from going on illicit shopping sprees.

New error-correcting codes guarantee the fastest possible rate of data transmission

Error-correcting codes are one of the triumphs of the digital age. They’re a way of encoding information so that it can be transmitted across a communication channel — such as an optical fiber o ...

The power of estrogen -- male snakes attract other males

A new study has shown that boosting the estrogen levels of male garter snakes causes them to secrete the same pheromones that females use to attract suitors, and turned the males into just about the sexiest ...

Anonymous knocks CIA website offline (Update)

The website of the Central Intelligence Agency was inaccessible on Friday after the hacker group Anonymous claimed to have knocked it offline.

Humans may have helped the decline of African rainforests 3000 years ago

(PhysOrg.com) -- Large areas of rainforests in Central Africa mysteriously disappeared over three thousand years ago, to be replaced by savannas. The prevailing theory has been that the cause was a change ...

Complex wiring of the nervous system may rely on a just a handful of genes and proteins

Researchers at the Salk Institute have discovered a startling feature of early brain development that helps to explain how complex neuron wiring patterns are programmed using just a handful of critical genes. ...