The impact of a mature quantum computing technology on society is expected to be tremendous, but there are many hurdles to overcome for up-scaling systems. To control and readout large numbers of physical qubits, cryogenic electronics may be necessary to reduce system cost and cabling as well as increase speed. One of the limitations of the design and integration of cryogenic electronics is the power consumption due to the limited cooling power available in the cryostat.
III-V HEMTs are already used in qubit readout LNAs due to their low power and low noise due to high electron mobilities at cryogenic temperatures. This project further demonstrated the scalability of quantum computers by cryogenic RF III-V electronics by a reduction of parasitic resistances with tensile strain Ohmic contacts which would impact future ultra-low power LNAs. In addition, we achieved multiplexing and switches based on the InGaAs HEMT platform which would enable dense and close integration with qubits since the circuits exhibited extremely low power, low charge injection, and fast switching.