Quantum Computer in the Solid State
Logo of Supracon AG

Supracon AG

Since its conception in 2001, it has been the company´s vision to bring superconducting electronics into industrial applications. The company has become a technology leader in the field of low and high temperature superconducting (sc) circuits and according electronics having already successfully established SQUID sensors in highly precise measurement setups (e.g., for accelerator physics, axion research, biomagnetism or geophysical exploration) and sc circuits such as primary voltage standards. SUPRACON already has many years of experience in system development and set-up. In addition to the provision of highly sensitive systems for geophysical exploration, the main business areas are primary voltage standards and the provision of technological services. In principle, the sensor technology is used under cryogenic conditions. For this reason, SUPRACON has developed and established a technology for cooling the voltage standard systems in recent years. This is also used in the research field of safety technology based on sc radiation sensors. The detection of hidden potential hazards at a distance of 50 m is the main focus here. As part of this research, SUPRACON has developed superconducting amplifiers and multiplexing methods that are also suitable for use in the field of controlling and reading out qubits. As part of the project, the technologies will be further researched and developed into products in the business areas.

Role within QSolid

The aim of this project is to research fundamental components for signal connection and readout of qubits in the millikelvin range for future quantum computers. The focus is on the development of cleanroom-based manufacturing technologies for flexible superconducting thin-film conductors as RF flex cables. Furthermore, innovative characterisation methods for these flex cables as well as noise-minimised microwave amplifiers based on superconductors for the readout of qubits are at the core of the subproject.

The central innovation consists of superconducting microwave connection components for transmitting the control and readout signals of qubits with minimal heat input and the highest integration level for a large number of channels. Scaling up to a high number of qubits is typically accompanied by an increased wiring effort, which on the one hand is cost-intensive and on the other hand negatively affects the operation of the quantum circuit (e.g., due to heat input, latency, reduced coherence times, channel crosstalk, etc.). Semirigid RF cables are currently used, which have a large design, are not multiport-capable, but have a high heat input due to the material properties. Due to the high heat load, quantum computers with a large number of qubits are not feasible. Flexible superconducting, thermally insulating, and highly integrable microwave cables that connect the cryogenic superconducting qubits to the periphery represent a solution option for scaling.

Such cables are thus a fundamental building block for quantum computing and also of central importance for the overall project applied for. The manufactured flex cables will be supplied to the consortium partners for system integration and evaluated and validated in the overall system. Furthermore, SUPRACON focuses on the research, development and implementation of methods and procedures for the characterisation of TWPAs.

Our vision for QSolid

It is Supracon’s vision to bring quantum technologies to industrial application since 2001 when the company was founded. In QSolid we can contribute to a really exciting project to build a superconducting quantum computer. This is a phantastic scientific challenge but also offers a lot of market potential. We are fully motivated to make QSolid a success.

- from Jens Kobow

Main contacts

Jens Kobow

Administrative project manager

Frank Hänschke

Technology development (clean room facility)

Marco Schubert

Senior researcher