An optical cavity like this could be used in a quantum engine
Max Planck Institute of Quantum Optics
A single atom within a reflective cavity could be sufficient to drive a piston in a tiny, quantum model of an engine.
The important function of any engine is that it converts warmth into work, which may then set mechanical elements into movement. For inside combustion engines, burning gasoline makes it develop and push on pistons, which ultimately outcomes in automotive wheels or turbine blades shifting. Álvaro Tejero on the University of Granada in Spain and his…