Royal Society Summer Science Exhibition - Schrödinger’s cat in a silicon chip

Schrödinger’s Frog

Very small things like atoms can behave in very surprising ways. Perhaps the strangest ability they have is that they can be in two places at once. They can also be both excited and relaxed at the same time, just like a guitar string can easily be made to sound two notes at once in an octave chord. This led to speculation by Erwin Schrödinger (one of the fathers of quantum physics) that a cat could be both alive and dead at the same time. Can you imagine how much fun you could have if you could be in two places at the same time?

Scientists from the University of Surrey's Advanced Technology Institute and University College London's London Centre for Nanotechnology are presenting their research at the Royal Society's annual Summer Science Exhibition, which opens today (5 July 2010).

The researchers have created interactive exhibits for the whole family including games, films and hands-on experiments. Visitors can learn how the researchers are making use of some of this quantum wave-particle weirdness to develop a new kind of computer: a quantum computer where the information can be both 0 and 1 at the same time. The exhibit explains how scientists have made electrons in a silicon chip behave like waves on a guitar string - destructively cancelling each other out and chiming in chords.

"We're hoping you will enjoy learning about the ideas behind our research - we are going to show you how quantum physics makes us change our perceptions of reality" said Professor Jim Al-Khalili. Professor Ben Murdin, who leads the team said "If you can understand how a simple musical instrument works, you can understand quantum physics. The exciting thing is that we are only now beginning to be able to really use its full power". Dr Neil Curson said "The real challenge is to be able to make devices with only a single atom at the heart. We are just starting to gain this atom scale control".

The scientists will be on hand at the exhibition which runs from 5 July to 10 July, to talk visitors through their research which ranges from control of ghostly quantum interferences to atomic engineering.

Figure:  Schrödinger's Frog. The picture shows the rows of individual atoms at the surface of a silicon crystal, imaged with the best microscope in existence, the scanning tunnelling microscope. Bulging out of the surface is a single foreign atom deliberately introduced to act as the world's smallest circuit component, the quantum bit. The legs of the "frog" are distorted neighbouring silicon atoms, pushed out of shape by the much larger inclusion.

For further information contact:
Nicola Kane
Press and Public Relations
The Royal Society, London
Tel: 020 7451 2508