World's smallest mirror created with 2,000 atoms
Paris-based researchers claim to have created the world's smallest functional mirror, using just 2,000 atoms of caesium. The mirror uses an optical fibre 400 nanometres in diameter, more than 200 times thinner than a human hair, to align the chain of caesium atoms to reflect the light. This may prove useful in building light-based circuits that will magnify computing speeds.