1. NQCP, a key research center within the Niels Bohr Institute at the University of Copenhagen, has validated SemiQon's cryogenically optimized CMOS RF-demultiplexers toward spin qubit measurement. The multiplexers would enable more qubits to be measured in a single cooldown.
2. The collaboration places SemiQon’s multiplexers inside the NQCP’s spin qubit platform, close to the qubits, at the cryogenic temperatures at which they operate.
3. Collaborating with leading research institutions such as the NQCP is crucial for the validation and further development of SemiQon’s cryo-optimized CMOS and allows researchers access to novel hardware.
4. As part of the collaboration, NQCP’s researchers have also characterized SemiQon’s superconducting microwave/RF switch to determine its suitability for experiments with superconducting qubits.
   

‍

The challenge

A useful quantum computer must read out many qubits at once, using control and readout electronics that may operate at temperatures near absolute zero. A dilution refrigerator has only a limited number of microwave and RF ports, yet each qubit depends on wiring to function.

The port bottleneck is one of the practical barriers to measuring more qubits per cooldown.  As part of the collaboration that first started in October 2025, SemiQon has delivered multiplexer chips to be used within the NQCP Spin Qubit Pilot Line, and the NQCP has committed to providing validations for the technology in the scientific community.

“When chips must be cooled one at a time, the process to characterize and to better understand the devices is very time consuming. Eventually, our goal is to validate several samples from a fab batch, or even an entire batch, simultaneously” explains Dr. Francesco Borsoi, Assistant Professor and Spin Qubit Pilot Line Lead at the Niels Bohr Institute.

The solution

One of the key benefits of spin qubit systems compared to other modalities is their scalability. However, the scale-up of control electronics and wiring are challenges that require attention across all qubit modalities.

"Every additional qubit multiplies the wiring problem inside the fridge. Cryogenic switching is how you break that constraint," explains Janne Lehtinen, CTO of SemiQon.

"We are still in the early stages, but this collaboration will show how our technology performs in a real qubit setup, close to the qubits, at the cryogenic temperatures at which they operate,” Lehtinen continues.

“To put it briefly, we aim at cooling many devices at once, which allows us to reduce the time spent on characterization, and in the first months, we have designed our measurements platform around that” Professor Borsoi clarifies.

Both Lehtinen and Borsoi see the mutual benefits of the partnership.

“From the start, the collaboration with SemiQon has been very synergetic. When research groups work with each other, there are typically elements of both collaboration and competition present. With a company, expectations are clear. In this case, both benefit when new products are put into real use,” Professor Borsoi describes.

The value

For SemiQon to continuously push the limits of its cryogenic electronics, putting the technology to real use is pivotal. At the same time, access to specialized hardware often allows research groups to avoid delays and focus on their core mission.  

For the NQCP, this mission is to develop fault-tolerant quantum computing hardware and quantum algorithms to tackle critical problems in life sciences.

“In the long run, our collaboration with the team at the NQCP contributes to a broader industry goal: developing scalable, high-speed measurement systems that are essential for the future of quantum computing," says Lehtinen.  

As the collaboration finishes its first year in September 2026, both SemiQon and the NQCP see room for the partnership to continue and to evolve. Conversations about the future are ongoing.

‍

Cryogenic electronics for different qubit modalities‍

The collaboration between NQCP and SemiQon covers two different modalities. Within the scope of the partnership, SemiQon’s cryogenically optimized CMOS devices have been delivered to two of NQCP’s research groups, one working on semiconducting and another on superconducting technology.

For the superconducting platform, first results from SemiQon’s superconducting microwave/RF switch have now been confirmed. A prototype of the switch was characterized to assess its suitability for superconducting qubit experiments.

‍

SemiQon’s first cryo-CMOS transistor launched in November 2024, with the technology now commercially available. The transistor achieves heat dissipation levels a thousand times lower than conventional room-temperature devices, enabling control and readout electronics to sit directly inside a cryostat with minimal thermal disturbance.