International Research Team Applies Metasurface Photonic Device Potential to Cold Atom Quantum Technology

Researchers at the UK Quantum Technology Hub Sensors and Timing, led by the University of Birmingham, have designed and implemented an approach for miniaturizing devices used in quantum sensing systems. A new technique for shrinking the size of quantum sensors drives the discovery, which relies on optical metasurfaces cutting the amount of space a laser delivery system needs to achieve functionality in quantum technology.

Sensing-device quantum technology works by controlling laser beams to engineer and manipulate atoms at supercold temperatures. This typically necessitates a vacuum chamber holding atoms for cooling. In this setup, a laser fires photons at the atoms while they are in motion, lowering their momentum and cooling them. Laser beams require precise positioning and space, however, and they must be positioned in pairs and set at angles.

Using an optical metasurface, the researchers diffracted a single laser beam into five unique, balanced, and uniform beams capable of supercooling atoms. The singular chip expedites the cooling process and exhibits the ability to replace the cumbersome structures that make up traditional cooling systems.

“The mission of the UK Quantum Technology Hub is to deliver technologies that can be adopted and used by industry,” said Yu-Hung Lien, lead author of the study introducing the research. “Designing devices that are small enough to be portable or [that] can fit into industrial processes and practices is vital. This new approach represents a significant step forward in this approach.”

The optical chip is 0.5 mm in width, resulting in a platform for forthcoming sensing devices to measure 30 cm³. The researchers said their next step will be to optimize device size and platform performance to achieve maximum sensitivity for each potential application.

The team completing and publishing the work consists of researchers from the University of Birmingham and SUSTech (China), as well as collaborators from Paderborn University (Germany). The research was published in Science Advances (www.doi.org/10.1126/sciadv.abb6667).