April 22, 2013

A new twist for quantum systems




Physicists at ETH Zurich have developed a method for precisely controlling quantum systems by exploiting a trick that helps cats to land on their feet and motorists to fit their cars into parking spots. In the longer run, the method could lead to the development of more reliable quantum computers.

To maneuver a car into a parking spot parallel to the road can be quite a challenge. It would be an easy task, of course, if only the vehicle could move sideways. As this is not possible, the sideways motion must be pieced together – sometimes elegantly, sometimes less so – in a series of forward and backward movements and turns on the steering wheel. Such a finely tuned sequence of movements also enables cats to almost always land on their feet after a free fall. Researchers at ETH Zurich have now used a similar principle for steering a quantum system into a desired state. This new type of control should be useful in situations in which quantum systems must be precisely controlled, not least in the context of quantum computers.