S-Transistors
S-Transistors develops superconducting transistors that combine the electrical gate control of a conventional transistor with the near-zero power dissipation of a superconductor, enabling electronics to operate natively at millikelvin temperatures inside dilution refrigerators. Its first products, scheduled for 2027, are low-loss multiplexers that switch multiple qubits and cryogenic devices onto a few measurement lines in real time, fitting existing cryostats without modification.
- Quantum Computing
- Semiconductor
- Hardware
Funding
Founders
Founder details are not available yet.
Product
Problem
Quantum processing units operate at millikelvin temperatures at the bottom of dilution refrigerators, but nearly all control and readout electronics remain outside. Each qubit requires its own coaxial line running the full height of the cryostat, making machines with a few hundred qubits cost €10–20 million in wiring, control electronics, and cooling infrastructure. The coldest stage can absorb only microwatts of power, so conventional transistors cannot operate there — yet superconducting digital logic lacks the tunability of a transistor, leaving no scalable building block for the cold electronics large-scale QPUs require.
Solution
Superconducting Transistor Company develops a device that combines the electrical gate control of a conventional transistor with the near-zero power dissipation of a superconductor, enabling ultra-low-power electronics to operate natively at the millikelvin stage next to the qubits. Its first products, scheduled for 2027, are low-loss superconducting transistor multiplexers that switch multiple qubits, test structures, and cryogenic devices onto a few measurement lines in real time. This directly addresses the wiring bottleneck: each dilution refrigerator has a fixed number of lines, and every cooldown is slow and expensive, so the number of devices that can be characterized per cycle is set by wiring, not by device quality. The multiplexer changes that ratio by turning a handful of measurement lines into many channels, fitting existing cryostats and wiring without modification.
Target Audience
Primary customers are quantum hardware teams and research groups operating dilution refrigerators who need to characterize qubits, test structures, and other cryogenic devices more efficiently per cooldown cycle.
Features
- Superconducting transistor platform that combines electrical gate control with near-zero power dissipation, operating natively at millikelvin temperature
- Low-loss multiplexers that switch multiple qubits and cryogenic devices onto few measurement lines in real time
- Designed to fit existing cryostats and wiring without requiring hardware modifications
- Enables characterization of more devices per cooldown, reducing the number of expensive cooldown cycles needed
- Architecture positioned as scalable for future fault-tolerant quantum systems, avoiding the one-line-per-qubit scaling wall
- World's first wafer-scale superconducting transistors on a production-ready 150 mm pilot line with more than 98% yield
- Patent-pending fabrication process and device architecture