Electronic circuits operating at low temperatures (4 K or even lower) have great importance for the functioning of quantum devices at cryogenic temperatures. Installing classical on-chip electronics nearby the device has its promises to improve the signal to noise ratio with enhanced frequency bandwidth by avoiding lengthy cabling to room temperature apparatus. For future quantum computers with unprecedented calculation capacity, cryogenic electronics enables fast and efficiently controlled manipulation and read-out of a large number of quantum bits (qubits). In addition, the thermal dissipation of the electronics is an issue in view of the limited cooling capacity of the used dilution refrigerators for attaining mK temperatures.
In a collaboration between CEA-LETI and CEA-IRIG, we designed classical electronics by making use of the low-temperatures transistor characteristics for their implementation into cryogenic design rules. The circuits were fabricated with the 28nm-FDSOI technology at the industrial STMicroelectronics foundry. It is our goal to have a toolbox of basic cryogenic circuit elements, such as multiplexers, level shifters, low-noise amplifiers, rf generators, or digital-analog converters, in order to develop dedicated on-chip electronics for massively controlling and reading silicon CMOS-based qubits.