ESPOO, Finland, Aug. 31, 2026 — Finnish startup S-Transistors has raised €2.6 million in pre-seed funding to commercialize a new class of superconducting transistors and to develop “quantum motherboards” for energy- and cost-efficient orchestration of cryogenic quantum computers. The company originates from VTT Technical Research Centre of Finland and says its technology is already available at wafer scale.
Superconducting transistors and the scaling challenge
S-Transistors aims to address a key bottleneck in scaling cryogenically cooled superconducting quantum computers: the current reliance on power-hungry, room-temperature electronics and separate wiring for each qubit. Those approaches limit how large quantum processing units (QPUs) can grow because excessive heat and bulky cabling complicate cryogenic operation. The startup positions superconducting transistors as devices that combine transistor-like computational functionality with the near-zero power dissipation of superconductors, making them compatible with the millikelvin environment of quantum processors.
“Today’s efforts in scaling cryogenic quantum computers have delivered tremendous progress, with several practical use cases already demonstrated. However, further scaling is approaching a hard wall, as it still relies on power-hungry room-temperature electronics and separate wiring for each quantum bit (qubit) – both used to operate the quantum computer and link it to the outside world. The clearest path forward, for superconducting quantum computers in particular, is to bring the classical control and interface hardware down into the cryostat, right next to the quantum chip kept cold to protect its fragile quantum states. The catch is that such integration is extremely demanding in power dissipation, speed, and energy efficiency,” says Dr. Heorhii Bohuslavskyi, Co-founder and CEO of S-Transistors. “Superconducting transistors are exactly that missing piece of hardware for large-scale, energy-efficient quantum computing.”
Product roadmap, funding use and early market approach
The pre-seed round was led by Lifeline Ventures and joined by an angel investor. S-Transistors plans to use the funds to develop several product prototypes for cryogenic signal control and handling, to set up its own cryogenic laboratory, to establish a manufacturing pilot line for integrated circuits based on superconducting transistors, and to grow its team.
The company’s first product will be a superconducting-transistor-based multiplexer designed to plug into existing cryogenic setups and accelerate development and prototyping of quantum devices. S-Transistors says the multiplexer will ship to early customers and strategic partners within the company’s first year of operation and that it represents a logical step toward the broader “quantum motherboard” vision.
“When you think about it, the transistor is the most mass-manufactured device in human history. By combining the transistor functionality, with its unparalleled computing potential, and the superconducting property of near-zero power dissipation in a single device, we can reach a completely new level of energy-efficient cryogenic computing. In the near term, this already solves the cryogenic signal routing and delivery problems the superconducting quantum computer, but the real vision is the quantum motherboard: a completely new platform for scaling quantum computers, operating at mK temperatures, and controlling the operation of qubit-based QPU,” says Dr. Andrey Generalov, Co-founder and CTO of S-Transistors.
S-Transistors also highlights broader potential beyond quantum computing, noting applications in classical and energy-efficient computing, artificial intelligence and high-performance computing hardware, spacecraft electronics, and fundamental particle detectors. The company combines patent-pending fabrication and early-product circuit architectures with more than 50 years of combined experience across microelectronics, cryogenics, quantum electronics and advanced manufacturing.
“S-Transistors is one of those rare companies built around a genuinely new piece of fundamental technology that could become an enabling layer for an entire industry. As quantum computers scale from hundreds or thousands of qubits toward commercially useful machines, we believe superconducting transistors can become a critical part of the hardware stack that makes that scaling possible,” says Jyri Engeström, Partner at Lifeline Ventures.
“Our strategy at VTT is to shorten the journey from idea to pilot, from pilot to commercial solution. We will continue to be a part of S-Transistors’ journey as the company approaches the manufacturing phase. S-Transistors’ superconducting transistor technology will allow us to reach the point where quantum computers finally provide real-world value,” says Erja Turunen, Executive Vice President at VTT.
