Towards practical and massively parallel quantum computing emulation for quantum chemistry

Abstract

Quantum computing is moving beyond its early stage and seeking for commercial applications in chemical and biomedical sciences. In the current noisy intermediate-scale quantum computing era, the quantum resource is too scarce to support these explorations. Therefore, it is valuable to emulate quantum computing on classical computers for developing quantum algorithms and validating quantum hardware. However, existing simulators mostly suffer from the memory bottleneck so developing the approaches for large-scale quantum chemistry calculations remains challenging. Here we demonstrate a high-performance and massively parallel variational quantum eigensolver (VQE) simulator based on matrix product states, combined with embedding theory for solving large-scale quantum computing emulation for quantum chemistry on HPC platforms. We apply this method to study the torsional barrier of ethane and the quantification of the protein–ligand interactions. Our largest simulation reaches 1000 qubits, and a performance of 216.9 PFLOP/s is achieved on a new Sunway supercomputer, which sets the state-of-the-art for quantum computing emulation for quantum chemistry.

Quantum computing with trapped ions: a beginner’s guide

“…Until then, we remain in the era of noisy intermediate-scale quantum (NISQ) devices, and it is difficult to predict which platform will emerge victorious, if any. Nevertheless, physicists have already used NISQ devices to simulate physical problems and provided proof-of-concept implementations (for example, see [77][78][79]), and we look forward to further developments in the near future.…”

Applications of noisy quantum computing and quantum error mitigation to “adamantaneland”: a benchmarking study for quantum chemistry

“…Notable recent progress includes the development of new variational ansätze, 34–36 adaptations of spatial and spin symmetries, 37 optimizing qubit measurement efficiency, 38–41 techniques for reducing qubit resources, 42,43 error mitigation strategies, 44,45 and development of quantum simulators. 46 Researchers are actively leveraging these algorithmic advancements to assess the potential of VQE in studying molecular systems, including applications related to electronic ground states, 47–49 excited states, 50–52 and vibrations. 53–55…”

TenCirChem: An Efficient Quantum Computational Chemistry Package for the NISQ Era

“…For such simulators, the largest simulated UCC circuit to date contains fewer than 30 qubits . In contrast, matrix product state (MPS) simulators are able to tackle larger circuits, with around 100 qubits , possible. Among the packages mentioned above, QisKit , PennyLane , and Q 2 Chemistry have implemented the MPS simulator.…”