Powering quantum science in Japan: how industry-grade laser solutions support groundbreaking research

The OHMORI Group at the Institute for Molecular Science (IMS), a Japanese governmental research laboratory, aims at broadening our understanding of the quantum world by trying to fully harness the wave properties of atoms and molecules with light. The team has been a satisfied customer of Exail for several years, for modulation solutions and for turnkey laser systems dedicated to quantum technologies.

“Our research team works on quantum simulation experiments with ultracold arrays of Rydberg atoms, as well as experiments to demonstrate ultrafast quantum gates. For these two main topics, we rely on Exail’s modulation solutions for fast and precise control of our lasers, and Exail’s fully integrated laser system to reliably and routinely manipulate atoms.“ Sylvain de Léséleuc, Associate Professor at IMS.

Ultrafast qubit gate manipulation with Exail’s electro-optic modulators

In 2022, Sylvain de Léséleuc’s team achieved a breakthrough by attempting the world’s fastest two-qubit gates – a fundamental operation for quantum computing – between two single atoms. To push further the ultrafast manipulation of Rydberg atoms, they then turned to Exail’s intensity modulators for switching lasers on and off at extreme frequencies—every few hundred picoseconds. This requires leveraging the telecom industry’s expertise in intensity modulation, combined with Exail’s capability to tailor electro-optic modulators to the specific 780 nm wavelength. The electro-optic solution replaced acousto-optic systems, which couldn’t achieve the necessary modulation speeds.

In another cutting-edge experiment, Exail’s fiber-based phase modulators are instrumental in implementing the Pound-Drever-Hall (PDH) technique, a powerful active laser stabilization method that locks the laser’s emission frequency to the resonance of an ultra-stable, high-finesse reference cavity.

The research team continues to work closely with Exail on new, customized developments aimed at encoding information into the laser at sub-nanosecond scales to manipulate the electronic cloud surrounding atoms.

“We expect to overcome new technological hurdles in the coming years, thanks to faster electro-optic modulators capable of handling higher power. Given the remarkable advancements we’ve witnessed recently, we trust manufacturers like Exail to continue delivering modulators with even greater stability. From an academic perspective, having direct contact with a manufacturer’s engineering team, as we do with Exail, is invaluable—it allows us to receive components tailored to our specific, often unconventional, needs. Additionally, knowing that Exail manufactures doped optical fibers, we can envision your company soon offering integrated solutions that combine modulation and amplification functions.” Sylvain de Léséleuc

Facilitating quantum technology advancements with Exail’s intelligent laser systems

The team of Sylvain de Léséleuc is also focusing on developing a quantum computer based on cold atoms. The team relies on Exail’s integrated laser system to cooldown atoms. Once cooled and arranged in an atomic array, the atoms serve as manipulable qubits for quantum computation.

“For the cooling process, we don’t necessarily need the most powerful laser, but we do require a laser with a broad tuning capability. This means multiple (6-7) laser outputs that can be dynamically adjusted in terms of intensity, frequency, or switched on and off as needed.” Sylvain de Léséleuc

In the past, months to years of lab workforce were usually necessary to develop an equivalent laser system in-house—a task that, while technically demanding, did not present any new scientific challenges. This represented a significant drain on valuable research time and resources. Recognizing this, the team turned to Exail’s turn-key industry-grade lasers. Originally developed for quantum gravimetry using cold atoms, the solution has already proven relevant and mature. Several lasers, precisely calibrated to the needs of the research group, are now used to cool down Rubidium atoms efficiently, freeing up the scientists to focus on more critical research.

“Now, we simply connect the output fibers to our experiment, and we control everything from a computer. It works all the time, which is very satisfying.” Sylvain de Léséleuc

Exail is glad to participate in expanding the frontiers of quantum technologies in Japan. The OHMORI Group is now involved in a cold-atom quantum computing research project called Moonshot, funded by the Japan Science and Technology Agency’s (JST). The project aims at developing a large-scale and high-coherence fault-tolerant quantum computer with dynamical atom arrays. It is a move towards Japanese sovereignty in the field of quantum computing. Several private companies are partners of the project for the potential commercialization of this preparatory platform.