The Perfect Amplifier – but only sometimes..


Speaker: Professor Tim Ralph (University of Queensland)
Date: 27th August 2010

The ability to amplify small signals is crucial to all manner of communication, computation and metrology devices. However when the ultimate limits of such technologies are approached it is found that the rules of quantum mechanics do not allow the perfect amplifier to be built. I will explain why this restriction exists and discuss the recent discovery of a loophole that does allow perfect amplification at the quantum limit – but only if it doesn’t always work. I will describe the applications of this non-deterministic quantum amplifier and recent experiments performed in Australia and overseas to demonstrate it.