18 Aug 2021
To fabricate ultra-low loss silicon nitride circuits for generating “error-corrected qubits”.Xanadu, a full-stack photonic quantum computing company and nanoelectronics research center imec have announced a partnership to develop photonic qubits based on ultra-low loss silicon nitride (SiN) waveguides.
Xanadu is developing a novel type of quantum computer, one based on photonics. The photonic qubits are based on squeezed states – a special type of light generated by chip-integrated silicon photonic devices.
This approach uses photons to carry information through photonic chips. Xanadu’s photonic approach offers the benefits of scalability to one million qubits via optical networking, room temperature computation, and the ability to leverage fabrication R&D centers – such as imec.
“One of the most critical challenges in building a photonic quantum computer is finding the right fabrication partner that can simultaneously deliver cutting-edge process development and volume production of high performing photonic chips,” said Zachary Vernon, who heads Xanadu’s Hardware team.
“Imec is one of the few semiconductor R&D centers that does advanced technology R&D as well as volume manufacturing on 200mm and 300mm lines, as well as volume manufacturing on their 200mm line. It can deliver up to a thousand wafers per year per customer on a few platforms including ultralow-loss photonic platforms. The seamless transfer offered by imec of new processes to production is especially critical for rapid scaling of our technology.”
Competing platforms for photonic quantum computing traditionally rely on single photon sources made from silicon waveguides, which suffer from non-deterministic operation. Using silicon nitride enables the generation of squeezed states, which replace single photons as the basic resource for synthesizing qubits.
Squeezed states are deterministically generated, and can be used to distill error-resistant qubits called “GKP states”. When multiplexed and implemented in Xanadu’s architecture, these offer a more promising path to fault-tolerant quantum computing.
Amin Abbasi, business development manager at imec, commented, “We are pleased to see that imec’s wafer-scale low loss SiN photonics platform, initially developed for communication, is finding its way towards other advanced applications, like quantum computing.”
Philippe Helin, specialty components program manager at imec, added, “Xanadu’s mission to build photonic quantum computers matches perfectly with our track record of and commitment to pushing the leading edge of integrated technologies.”
Christian Weedbrook, Xanadu Founder and CEO, said, “Our ultimate mission is to build quantum computers that are useful and available to people everywhere. To do this we have the ambitious goal of reaching one million qubits using photonics. Working with imec will help us build the right foundation based on fault tolerance and error-correctable qubits.”
Xanadu offers cloud access to both photonic quantum hardware and software solutions over its Xanadu Cloud platform. It recently announced a $100 million funding round led by Bessemer Venture Partners giving a total of $145 million raised thus far.