📄 Showing the "Simple" version — "Advanced" is not ready yet. Add it to favorites to help prioritize it. Ask for the full read

A regular motor burns fuel and wastes a ton of energy as heat — that's dictated by the laws of thermodynamics. A quantum engine does it differently: its fuel isn’t heat, but a perfect rhythm. Physicists call this rhythmic precision quantum coherence. Think of it like an orchestra where every musician keeps flawless tempo — but here, the entire orchestra is just a single electron.

Scientists used a diamond with a carbon defect, which hosts that precise electron. Using a laser probe, they monitored its state, like tapping into a tiny battery. The electron was charged with a microwave field — imagine setting an ideal musical beat that makes the particle “dance.” The stored energy then turned into useful work. Remarkably, the same electron was both the motor and the battery.

After several cycles, the quantum machine produced nearly double the work of its classical heat-based twin. This success opens the door to nanomotors that will only operate at full power in the quantum regime.

Original abstract

as written by the authors arXiv:2511.06096

Heat engines convert thermal energy into mechanical work. We here report the experimental realization of a fully quantum engine that converts quantum coherence into work. A single solid-state spin in diamond is fueled by a coherent bath and cyclically stores energy in a spin quantum battery. We establish quantum-enhanced performance by showing that almost 200$$\%$$ more work is produced after a few cycle compared to the corresponding classical engine. We obtain concrete criteria for successful coherence-to-work conversion, and highlight the importance of a coherent motor-battery interaction. This device harnesses nonclassical features during all stages of its cycle, and demonstrates the functionality of a nanomachine whose parts are all quantum coherent.