Quantum Interface Simultaneously Extracts Photons from 10 Atoms: Osaka University, NICT, and Hamamatsu Photonics Set World Record for Multiplexing

Explanation

One approach in quantum computers arranges neutral atoms one by one using optical tweezers to serve as qubits. About 10,000 atoms can be arranged in a single device, making this one of the leading approaches. However, achieving "fault tolerance" — computing while automatically correcting errors — requires more than 1 million qubits, more than a single device can provide. Multiple devices would need to be connected optically, and that connection has become a bottleneck.

Connecting atoms with light requires guiding the photons emitted by atoms, one by one, into optical fibers. Until now, the main approach has been to prepare one optical system per atom, meaning the number of devices increased along with the number of atoms.

A team from Osaka University, NICT, and Hamamatsu Photonics succeeded in simultaneously receiving photons from 10 atoms arranged a few micrometers apart using a 32-channel integrated optical waveguide array, detecting all 10 in parallel. By aligning the arrangement of the atoms with the arrangement of the waveguides, they achieved multiplexing without increasing the number of devices. A multiplexing degree of 10 is a world record, and the design could reportedly be extended to about 100-fold multiplexing.

To scale a device holding 10,000 atoms up to the 1-million scale, the multiplexing degree of the "quantum optical interface" that connects devices together at high speed becomes critical. This result of 10 marks the first step toward that goal.

The paper was published on August 31, 2026, in Optica, a journal published by Optica (formerly the Optical Society, OSA).