A Fully Integrated Cryo-CMOS SoC for State Manipulation, Readout, and High-Speed Gate Pulsing of Spin Qubits

This article presents a fully integrated Cryo-CMOS system on chip (SoC) for quantum computing. The proposed SoC integrates a radio frequency (RF) pulse modulator for qubit state manipulation, a multi-tone signal generator and a coherent receiver for qubit state readout, and 22 DACs for high-speed voltage pulsing of qubit gates. By adopting frequency division multiplexing and direct digital synthesis (DDS), the RF pulse modulator can control up to 16 qubits over a single RF line, and the readout receiver can detect the state of up to six qubits simultaneously. The proposed SoC also integrates a microcontroller for low latency on-chip signal processing and increased flexibility in implementing quantum instruction sets. A detailed analysis of qubit-state readout fidelity and the impact of finite DAC resolution on two-qubit gate fidelity is also included in this article, together with an electrical specification summary. The SoC is implemented in Intel's 22 nm FFL fin field-effect transistor (FinFET) process, and it is characterized both at room and 4 K temperatures. The performance of each specific block is measured, with the readout characterized in a loop-back configuration. Generation of the control signals required for a full Rabi oscillation experiment is also demonstrated. This article also describes the cryogenic thermalization techniques used to integrate the SoC in the dilution refrigerator and shows temperature measurements during operation.

Automated summary

This article presents a fully integrated Cryo-CMOS system on chip (SoC) for quantum computing, which includes an RF pulse modulator, a signal generator, a coherent receiver, and DACs. The SoC also integrates a microcontroller for low latency signal processing and increased flexibility in implementing quantum instruction sets.