Pioneering cold-atom based quantum technologies

Published on October 17, 2023 – News

The quantum sensing activity of Exail, started 12 years ago in the very footsteps of Alain Aspect, 2022 physics Nobel prize, is the world’s leader in industry-grade quantum sensors based on laser cooled atoms.

Today, Exail quantum sensors are operated worldwide by non-specialists, from the top of Mount Etna to Antarctica. The development of dedicated intelligent frequency-stabilized laser systems (ILS) and Integrated micro-optics benches (iMOB) holds the key to such success. This state-of-the-art range of technologies is now available for a broader range of users. Beyond quantum sensors, Exail’s photonics solutions enable real applications in all quantum technology fields, both for academic laboratories and for the industry. Following the outstanding developments and field deployments of quantum gravity sensors, laser-cooled atoms are today one of the most mature and promising physical platforms to implement quantum computing and long-distance quantum communication.

Exail’s ILS now stands as a flagship solution for quantum systems manipulation. It indeed integrates a range of in-house components and sub-systems (iMOB), offering innovative and reliable solutions to unleash the use of quantum technology platforms. From design to manufacturing, Exail masters the complete production chain of such integrated ILS laser systems. The company also provides specialty fibers, bragg gratings, high speed modulation solutions and micro-optics assemblies. Exail leverages on both this industrial capacity and on the fruitful collaborations with leading research labs it has nurtured over the years.

Exail’s field-proven solutions now cover a wide range of quantum applications, from the deep sea (in 2022, Exail and researchers from the LP2N lab demonstrated the first 3-axis quantum inertial sensor that allows to continuously measure the acceleration in 3 dimensions and for any orientation of the sensor, an important step towards the development of a drift-free inertial navigation system) to outer space (Exail is involved in the CARIOQA-PMP European project which aims at developing a space grade quantum gravimeter for Earth and climate monitoring).

Efforts deployed by academic laboratories and companies worldwide to develop quantum processors are tremendous. Exail’s innovative and reliable photonics components and systems are there to ensure faster development, from fundamental research to commercially available machines, and allow increasingly complex set-ups to be developed and ran. Whether they rely on photons, neutral atoms, trapped ions, NV-centers to implement quantum computing or quantum simulation, Exail’s iMOBs and modulation solutions will help reach the most ambitious goals.

Turn-key laser systems for quantum technologies and laser-cooled atoms

Exail intelligent laser systems (ILS) is a new generation of compact and agile laser system offering precise control of lasers amplitude, phase, and absolute frequency with fast tunability. The ILS laser Series is mainly dedicated to manipulating rubidium atoms with 780 nm laser light. However, other wavelengths for other species can be addressed and a wide variety of configurations are available.

The laser architecture is based on the use of slave lasers, phase-locked to a master laser whose frequency is actively stabilized on an atomic transition using saturated absorption spectroscopy. The laser systems are equipped with dedicated ultra-low-noise electronics developed by Exail, on-board computer and power supply to offer ultra-low noise laser light, agile and precise frequency control, industry-grade integration and remarkable robustness, and user-friendly operation. These laser systems can also integrate an ultra-low noise microwave synthesizer.

The ILS systems are based on C-band fibered telecom optical components (i.e seed lasers), a proven robust and reliable technology. The laser light at telecom wavelength (around 1560 nm) is amplified and frequency-doubled to generate the required wavelength. This approach gives access to a wide variety of high performance fibered optical components, originally developed for high-bit-rate optical communication systems.

The laser systems provided by Exail feature state-of-the-art optical performances that meet the stringent demands of cold-atom physics and atom interferometry. On the optical domain, careful measurements show a typical linewidth of 50 kHz at 780 nm and a typical frequency stability of the different slave lasers of 50kHz rms over days.

With Exail’s ILS, the performances of state-of-the-art quantum physics experiments can be accessible to a much broader spectrum of users outside of academic laboratories. Indeed, no optical alignment, no mechanical assembly, no manual adjustment is required prior to operation and the installation can be done in 10 minutes. The frequency locking of the master laser and the phase locking of the slave lasers are automated and managed by the on-board computer. The frequency lock and the phase locks remain locked for months without any action required from the user. It is robust with regard to temperature variations and vibrations.

The dedicated and user-friendly data acquisition and system controller software allows an easy access to automated starting and self-calibration procedures, and to remote access and real-time data retrieval. The final asset of the ILS system is its small footprint, as it can be integrated in 19’’ rack cabinets and feature output fibers whose length can be of several meters.

Turning your photonic lab experiment into a compact and robust system with the iMOB Series

It is well known, photonic laboratory experiments can be tricky to handle as they require regular realignment, in particular when turned on and when the system is heating up. Exail has developed the iMOB to help researchers in this situation. iMOB is a free-space micro-optical bench (fibered in entrance and output) built using a fully active alignment method that has been proven reliable for telecom application, space application, and that is perfectly suited for laboratory applications. iMOB systems offer stability and reproducibility of the measurements, while being compact and transportable, and they can integrate a wide range of optical functionalities.

One of the biggest challenges in optics is to manage the light once it has been emitted. Optical fiber is often the preferred solution as it is the easiest way to manage a laser beam. Still though, depending on the application’s wavelengths, free space optics might be necessary in order to perform the effect needed for certain functionalities that are not easily compatible with a fiber. Exail micro-optics technology was developed and was first acknowledge by a Telcordia norm to be compatible with telecom applications. Exail leverages this know-how in the 1550 nm wavelength range and offers today the iMOB series as an answer to the markets
needs of today.

Exail expertise in the direct assembly of micro-optics makes it easy to integrate switches, frequency shifters, or splicing combining functions in iMOB benches. It can perform the requested functions by using quarter waveplates, half waveplates, acousto-optics modulators, shutter blades, mirrors and of course lenses. As the laser beam is collimated with our own methods, powers up to a few Watts can be handled. iMOB also relies on Exail’s gluing technology which was Telcordia approved, and more recently qualified for space applications in the 1550nm range.