Quantum computing a step nearer with silicon research breakthrough

The findings - published in Nature - marks a significant step towards the making of an affordable 'quantum computer'. A team from the University of Surrey, UCL (University College) London, Heriot-Watt University in Edinburgh, and the FOM Institute for Plasma Physics near Utrecht have created a simple version of 'Schrodinger's cat' – which is simultaneously both 'dead' and 'alive' - in the cheap and simple material from which ordinary computer chips are made. "This is a real breakthrough for modern electronics and has huge potential for the future," explained Prof Ben Murdin, photonics group leader at the University of Surrey. "Lasers have had an ever increasing impact on technology, especially for the transmission of processed information between computers and this development illustrates their potential power for processing information inside the computer itself." Prof Murdin's team used a far-infrared, very short, high intensity pulse from the Dutch FELIX laser to put an electron orbiting within silicon into two states at once - a 'quantum superposition' state. "We then demonstrated that the superposition state could be controlled so that the electrons emit a burst of light at a well-defined time after the superposition was created," Murdin explained. "The burst of light is called a photon echo; and its observation proved we have full control over the quantum state of the atoms." Murdin believes that the development of a silicon based quantum computer may be only just over the horizon. He continued: "Quantum computers can solve some problems much more efficiently than conventional computers - and they will be particularly useful for security because they can quickly crack existing codes and create un-crackable codes. The next generation of devices must make use of these superpositions to do quantum computations. Crucially, our work shows that some of the quantum engineering already demonstrated by atomic physicists in very sophisticated instruments called cold atom traps, can be implemented in the type of silicon chip used in making the much more common transistor."