A “quantum bath” puts quantum entanglement on autopilot

Physicists have demonstrated a new way to entangle distant quantum bits without the constant measurements and active control normally required. The team created a “quantum bath,” a shared environment filled with correlated microwave photons that automatically pushes separated qubits into an entangled state and helps keep them there. The experiment confirms a theoretical prediction made more than 20 years ago and could offer a simpler way to connect modules in future quantum computers.

A “quantum bath” puts quantum entanglement on autopilot. A “quantum bath” puts quantum entanglement on autopilot Science News from research organizations A “quantum bath” puts quantum entanglement on autopilot A 20-year-old quantum prediction has finally been demonstrated, using a bath of correlated light to automatically entangle distant qubits. ISTA PhD student and the study’s first author, Alejandro Andrés-Juanes, in the lab.

Until now, creating this kind of connection has generally required active control and repeated measurements. Physicists at the Institute of Science and Technology Austria (ISTA) have now demonstrated a fully autonomous alternative based on a "quantum bath" made from correlated particles of light. Published in Physical Review X, the experiment provides the first demonstration of a prediction proposed more than 20 years ago.

The approach could eventually offer a new foundation for practical quantum technologies.