FPGA-based electronic system for the control and readout of superconducting quantum processors

TLDR

Electronic systems for qubit control and measurement bridge quantum programming and processors, and the rapid advancement of superconducting circuits demands synchronized, low‑latency, low‑noise electronics. The authors present an FPGA‑based electronic system featuring a distributed synchronous clock and trigger architecture. The system implements real‑time digital signal processing in the FPGA to provide precise timing control, arbitrary waveform generation, IQ demodulation for qubit state discrimination, and real‑time qubit‑state‑dependent trigger signals for feedback and feedforward control. The system achieves synchronous qubit control with ~5 ps jitter, reduces feedback/feedforward latency to 125 ns—well below qubit decoherence times—and demonstrates low‑noise performance on a fluxonium quantum processor.

Abstract

Electronic systems for qubit control and measurement serve as a bridge between quantum programming language and quantum information processors. With the rapid development of superconducting quantum circuit technology, synchronization in a large-scale system, low-latency execution, and low noise are required for electronic systems. Here, we present a field-programmable gate array (FPGA)-based electronic system with a distributed synchronous clock and trigger architecture. The system supports synchronous control of qubits with jitters of ∼5 ps. We implement a real-time digital signal processing system in the FPGA, enabling precise timing control, arbitrary waveform generation, in-phase and quadrature demodulation for qubit state discrimination, and the generation of real-time qubit-state-dependent trigger signals for feedback/feedforward control. The hardware and firmware low-latency design reduces the feedback/feedforward latency of the electronic system to 125 ns, significantly less than the decoherence times of the qubit. Finally, we demonstrate the functionalities and low-noise performance of this system using a fluxonium quantum processor.