Researchers Entangle a Glass Bead With a Light Beam
Laser light trapped in an optical cavity held and cooled the bead, which then became quantum-entangled with the beam, according to Ars Technica.
Researchers have achieved quantum entanglement between a light beam and a glass bead, according to Ars Technica. The work links a macroscopic mechanical object to light at the quantum level.
To do it, the team used laser light to suspend and cool the glass bead with optical tweezers. The laser light was confined between a pair of mirrors in an optical cavity, with the bead positioned at its center.
The result rests on the combination of two tools: the optical tweezers that trap and cool the bead, and the cavity that keeps the light field tightly confined around it. Entanglement between the beam and the bead means the two can no longer be described independently of each other.
Ars Technica reported the entanglement between the light beam and the glass bead. No further details, including publication venue or date, were given.
Quick answers
What did researchers entangle?
They entangled a light beam with a glass bead.
How was the glass bead held in place?
Laser light used as optical tweezers suspended and cooled the bead, with the light confined between mirrors in an optical cavity and the bead at the center.
Why does the optical cavity matter?
It confined the laser light between a pair of mirrors around the trapped bead, the setup in which the entanglement was achieved.