Exploiting Different Levels of Parallelism in the Quantum Control Microarchitecture for Superconducting Qubits
Mengyu Zhang, Lei Xie, Zhenxing Zhang, Qiaonian Yu, Guanglei Xi, Hualiang Zhang, Fuming Liu, Yarui Zheng, Yi-Cong Zheng, Shengyu Zhang · 2021
As current Noisy Intermediate Scale Quantum (NISQ) devices suffer from decoherence errors, any delay in the instruction execution of quantum control microarchitecture can lead to the loss of quantum information and incorrect computation results. Hence, it is crucial for the control microarchitecture to issue quantum operations to the Quantum Processing Unit (QPU) in time. As in classical microarchitecture, parallelism in quantum programs needs to be exploited for speedup. However, three challenges emerge in the quantum scenario: 1) the quantum feedback control can introduce significant pipeline stall latency; 2) timing control is required for all quantum operations; 3) QPU requires a deterministic operation supply to prevent the accumulation of quantum errors.