A group of physicists recently built the smallest engine ever created from just a single atom. Like any other engine it converts heat energy into movement — but it does so on a smaller scale than ever seen before. The atom is trapped in a cone of electromagnetic energy and lasers are used to heat it up and cool it down, which causes the atom to move back and forth in the cone like an engine piston.
The scientists from the University of Mainz in Germany who are behind the invention don’t have a particular use in mind for the engine. But it’s a good illustration of how we are increasingly able to replicate the everyday machines we rely on at a tiny scale. This is opening the way for some exciting possibilities in the future, particularly in the use of nanorobots in medicine, that could be sent into the body to release targeted drugs or even fight diseases such as cancer.