Qimax: Efficient quantum simulation via GPU-accelerated extended stabilizer formalism
Vu Tuan Hai, Bui Cao Doanh, Le Vu Trung Duong, Pham Hoai Luan, Yasuhiko Nakashima
TL;DR
This work tackles the challenge of efficiently classically simulating Clifford and near-Clifford circuits by advancing the extended stabilizer formalism with GPU-accelerated parallelism. The authors introduce Qimax, a three-mode system that uses instruction grouping and base-4 tensor encodings to accelerate stabilizer updates on GPUs, with v3 employing ragged tensors to reduce memory for non-Clifford expansions. Benchmarks show that Qimax, particularly in its v3 form, can outperform GPU-accelerated Qiskit and Pennylane in large-gate-count scenarios, though circuits with high stabilizer rank still scale as $O(4^n)$ versus $O(2^n)$ for state-vector methods. The approach broadens the practicality of stabilizer-based simulation for large Clifford and near-Clifford circuits and lays groundwork for integration with variational quantum algorithms and quantum machine learning workloads, especially where GPU parallelism is beneficial.
Abstract
Simulating Clifford and near-Clifford circuits using the extended stabilizer formalism has become increasingly popular, particularly in quantum error correction. Compared to the state-vector approach, the extended stabilizer formalism can solve the same problems with fewer computational resources, as it operates on stabilizers rather than full state vectors. Most existing studies on near-Clifford circuits focus on balancing the trade-off between the number of ancilla qubits and simulation accuracy, often overlooking performance considerations. Furthermore, in the presence of high-rank stabilizers, performance is limited by the sequential property of the stabilizer formalism. In this work, we introduce a parallelized version of the extended stabilizer formalism, enabling efficient execution on multi-core devices such as GPU. Experimental results demonstrate that, in certain scenarios, our Python-based implementation outperforms state-of-the-art simulators such as Qiskit and Pennylane.
