- Photonics
15 Dec 2025
Bringing Japan’s Leading Quantum Startup to Industrial Scale

Accelerating optical quantum computing with mature optical building blocks
OptQC’s mission is to make optical quantum computing practical and scalable by leveraging components already proven in the telecom industry—using them as-is to achieve reliability, cost efficiency, and rapid deployment.
While OptQC designs and assembles its own quantum hardware, it relies on partners such as Exail, recognized for its high-performance optical components and expertise in precision photonics.
"We know exactly which components we need, how to assemble them into our complex system, and how to control it precisely. Our relationship with Exail, a supplier of high-standard optical components, has been excellent. Personally, I’ve used Exail’s products for nearly a decade." — Warit Asavanant
Over the years, Asavanant has maintained close exchanges with Exail’s teams to stay informed about the latest technological advances. This led to the adoption of Exail’s high-impedance electro-optic modulator, now central to OptQC’s quantum computer design.
Exail’s low-frequency and high impedance modulators (MPX-LN-0.1) ensure precise phase, while broadband, low-voltage modulators (MPZ-LN-40) enable quantum processor programming at gigahertz rates. Together, they replace bulkier piezoelectric components that required higher voltages and complex stabilization.
"Programming an optical quantum computer is challenging because most control signals are digital, not optical. We encode information digitally, so we need efficient ways to bridge electrical and optical signals. Electro-optic modulators with high extinction ratios are the solution—and Exail excels in this area." — Warit Asavanant

Picture of Exail's phase modulators into OptQC's quantum computer
Building a full-stack, scalable commercial optical quantum computer
OptQC’s quantum computing architecture uses squeezed light pulses —phase-sensitive optical states whose quantum entanglement depends on ultra-precise phase monitoring at very high speeds. Each pulse carries quantum information in its phase, requiring optical components with minimal loss, exceptional phase stability, and fine-tuned controllability.

Schematic overview of OptQC's quantum optical computer, using Exail phase modulators and thermal stabilization box featuring a fiber coil.
Recently, OptQC began using a thermal stabilization box housing a several-hundred-meter-long fiber coil manufactured by Exail, designed to minimize temperature-induced phase drift. The coil hosts the optical pulses (qubits) through time-domain multiplexing at a 100 MHz clock rate.
Longer fibers often cause loss and instability, but Exail’s long experience with ultra-stable fiber coils for navigation systems (such as fiber-optic gyroscopes) ensures extremely low phase drift, meeting the stringent precision needs of quantum computing. This technology is promising for scaling OptQC’s systems, enabling more complex computations.
"Stabilizing a 200–300 meter fiber coil is already challenging. As we aim to go beyond that, collaborating with a company like Exail, with deep experience in this field, is essential." — Warit Asavanant
The first commercial OptQC quantum computer, integrating Exail’s modulators and thermalized fiber coils will be installed in a Japanese national lab and open to the public in April 2026 as a cloud-based platform. Users will be able to send computation requests online, with Exail’s components handling optical modulation and measurement.
Looking ahead, OptQC is already designing its second-generation quantum computer for 2027, aiming for greater compactness and scalability. The collaboration with Exail continues to deepen as both teams explore new ways to push optical quantum computing toward industrial scale.

Exail's thermal stabilization box featuring a fiber coil, connected to OptQC's quantum computer







