Quandela Launches Pilot Line for Qubit Devices

Quantum computing startup Quandela is establishing a pilot line for high-performance photonic qubit devices. Located at The Photovoltaic Institute of Île-de-France (IPVF), the line is expected to produce more than two thousand devices per year over the next two years.

With the pilot line’s opening, the company aims to boost device manufacturability and performance to accelerate the deployment of error-corrected quantum computers. At full capacity, it is projected to produce 10,000 devices per year with qubit density increasing to hundreds of devices per square millimeter.

The manufacturing plant features a qubit identification tool for testing of qubit properties, such as coherence time, at cryogenic temperatures in minutes, selecting the most performant qubits for further processing. By probing the quantum properties of hundreds of nanometer-sized structures and collecting high-volume data while mapping uniformity, this method provides fast feedback to optimize the fabrication process, officials with Quandela said. The process enables yields between 40% and 70% with low process variation.

Key to the company’s technology platform is its solid-state quantum dot photon source. Based on research by Quandela’s chief science officer, Pascale Senellart, senior researcher at Centre national de la recherche scientifique (CNRS) and professor at École Polytechnique, the sources boast an efficiency above 50%. According to Quandela, competing approaches employ light sources that generate photon-pairs with efficiencies of around 1% to 3%. Quandela’s approach has the potential to reach close to 100% as it continues to be refined.

Using a first-of-its-kind approach, a semiconductor quantum dot is included in a micron-sized optical cavity and aligned with under 100 nm precision, leveraging a proprietary technology that enables identification of randomly placed quantum emitters, according to the company. An optical lithography step is then undertaken at cryogenic temperature which allows the size and shape of the optical cavity to be tailormade to the chosen emitter.

Quandela opened its first quantum computer factory in June 2023, which allowed the company to deliver two quantum computers to industrial customers. The company raised ~$54.7 million last year to expedite its expansion and increase production.