An 11-bit 0.008 mm² charge-redistribution digital-to-analog converter operating at cryogenic temperature for large-scale qubit arrays

Abstract

This letter presents a cryogenic digital-to-analog converter (DAC) for controlling qubits in a large-scale quantum computer. The capacitor arrays composing a charge-redistribution DAC are miniaturized by effectively utilizing the cryogenic characteristics of extremely low noise and leakage. Furthermore, capacitor mismatches due to their small size are automatically corrected by a newly proposed calibration technique with a small area-overhead. Fabricated in 40 nm CMOS and measured at cryogenic temperature, the prototype 11-bit DAC achieved a very small area of 0.3 mm² and low power consumption of 5.8 μW, while realizing a non-linearity error within +/- 2 LSB.