An ASIC for the Superconducting Quantum Computer

We are developing two specialized control ASICs for quantum processors to enable the transition from today’s laboratory setups to compact, energy-efficient systems with high channel density.
Our work combines circuit design, system integration, and precision measurement under real-world conditions. In other words, we explore the entire system, from room-temperature control to in-cryostat integration, in-house.

Efficient Signal Processing at Room Temperature

The first chip operates at room temperature as an analog high-frequency transmitter.
An externally generated baseband signal is converted to the target frequency through a two-stage frequency translation, effectively suppressing unwanted spurious signals. The design focuses on compactness, higher channel density, and lower power consumption.
A particular challenge lies in filtering: integrated, space-saving filters simplify the design but may not always achieve the quality of external components. We therefore investigate whether the required signal integrity can be realized entirely on-chip or whether selected external filters should be used. At this stage, the baseband signal is generated outside the chip.

Control in the Cold – Electronics Close to the Quantum Processor

In the long term, we will move the electronics inside our cryostats and operate them at 4 Kelvin (−269 °C) in close proximity to the quantum processor.
Short, superconducting connections minimize losses, improve signal quality, and reduce heat input to the qubits, which is crucial for precise multi-channel control.
At these low temperatures, energy-efficient, low-noise circuits become possible, which significantly increases channel density.
We address challenges such as the lack of reliable simulation models for device behavior at 4 K through measurement-based modeling, as well as through the use of calibratable and adaptive circuits.
Due to the limited availability of cooling power, we rely on pulsed operation, rigorous power-down between pulses, and shared resources to minimize energy consumption.

Our researchers offer exclusive insights into their work, explain the background, and talk about what makes the project so special:

Quantum computers can solve problems faster than conventional high-performance computers. They therefore offer advantages for complex optimization in logistics and production. To achieve this, the hardware of a quantum computer must be controllable.

Read more in the online article.