Researchers have achieved macroscopic levitated rotors spinning freely for ten hours at room temperature, a milestone that significantly surpasses the coherence times of quantum rotors to date. This advance relies on suspending micrometric objects using optical and magnetic fields, minimizing friction and enabling the study of quantum mechanics in larger-scale systems. The ability to maintain rotation for such extended periods opens new avenues for exploring quantum phenomena in objects approaching the macroscopic world, an area where decoherence is usually a formidable obstacle.

The experiment uses highly oriented pyrolytic graphite (HOPG) rotors 300 µm in diameter, levitated in a partial vacuum of 10⁻⁶ mbar. Rotation is initiated by a laser and maintained in an environment where residual friction is drastically reduced. The key to success lies in the combination of optical and magnetic levitation, which allows for almost perfect isolation from the environment, preventing energy losses due to air resistance or mechanical supports. This precise control over the rotor is essential for observing its long-term behavior and for future quantum manipulations.

This achievement is crucial for the development of ultra-precise sensors and for exploring the boundary between quantum and classical mechanics. The ability to maintain coherence in macroscopic systems for such a long time could lead to the creation of more sensitive quantum gyroscopes or to the experimental verification of quantum gravity theories that predict effects on massive objects. Furthermore, it opens the door to investigating decoherence in complex systems, a fundamental step for quantum computing and metrology.