Caltech researchers have proposed a method of suppressing environmental noise (such as random thermal and mechanical vibrations) to observe quantum superposition and entanglement in progressively larger and more complex systems.

They propose to “levitate” a nanosphere using laser beams. The light that bounces back and forth between the mirrors both senses the motion of the sphere and is used to manipulate that motion at a quantum-mechanical level.

The researchers also propose a scheme to observe entanglement: sending a pair of initially entangled beams of light into two separate cavities, each containing a levitated sphere. Through a process known as quantum-state transfer, the entanglement properties of the light can be mapped onto the motion of the two spheres.