IEEE International Conference on Quantum Computing and Engineering (QCE)

An FPGA-based Quantum Control System with a Runtime Configurable Signal Generator

Taiqian Guo, Xiaorang Guo, Martin Schulz

Published Sep 15, 2024• 1 citation

Abstract

Signal generators for qubit control and measure-ments play a key role in quantum computers in terms of latency and scalability. Typically, the control pulses are generated by arbitrary waveform generators (AWGs) via preloaded lookup tables. However, this method lacks the flexibility to adjust phase and frequency in complicated programs, such as variational quantum eigensolvers (VAE) or pulse shape optimization al-gorithms. Therefore, we propose a quantum control system composed of a quantum control processor (QCP) and a run-time waveform-configurable signal generator in this work. For the signal generator, we developed a parallelized direct digital synthesis (DDS) structure to adaptively generate waveforms without requiring the entire waveform to be preloaded. The QCP, based on HiSEP-Q, is optimized with a deeper pipelined architecture to increase frequency and match the high bandwidth of signal generators. Additionally, we introduce a synchronization architecture in the QCP to manage uneven delays among different generation threads. Validated on the ZCU216 platform, our system achieves flexible signal generation with an average latency of 20 ns and reduces memory usage by more than 50%.

DOI: 10.1109/qce60285.2024.10412

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