Multilevel variational spectroscopy using a programmable quantum simulator

Han，Zhikun1,2,3; Lyu，Chufan4; Zhou，Yuxuan1,2,3,5; Yuan，Jiahao1,2,3,5; Chu，Ji1,2,3; Nuerbolati，Wuerkaixi1,2,3; Jia，Hao1,2,3; Nie，Lifu1,2,3; Wei，Weiwei1,2,3; Yang，Zusheng1,2,3; Zhang，Libo1,2,3; Zhang，Ziyan1,2,3; Hu，Chang Kang1,2,3; Hu，Ling1,2,3; Li，Jian1,2,3; Tan，Dian1,2,3; Bayat，Abolfazl4,6; Liu，Song1,2,3; Yan，Fei1,2,3,7; Yu，Dapeng1,2,3,5

2024

10.1103/PhysRevResearch.6.013015

Physical Review Research   影响因子和分区

2643-1564

Energy spectroscopy is a powerful tool with diverse applications across various disciplines. Variational quantum-classical algorithms based on programmable digital quantum simulators have emerged as promising approaches for conducting spectroscopy on various models using a single device, despite facing significant quantum and classical resource overheads. Here, we experimentally demonstrate multilevel variational spectroscopy for fundamental many-body Hamiltonians using a superconducting digital quantum simulator. By exploiting symmetries and the subspace search method, we achieve full spectroscopy for a four-qubit Heisenberg spin chain, yielding an average energy deviation as small as 0.13 from the theoretical values, assuming unity coupling strength. Our method, when extended to eight-qubit Heisenberg and transverse-field Ising Hamiltonians, successfully determines the three lowest-energy levels. In achieving the above, we introduce a circuit-agnostic compilation method that enhances the robustness of our simulator against signal crosstalk. Our study highlights the combination of the subspace search method and symmetry-assisted resource efficiency in variational quantum algorithms and lays the foundation for practical spectroscopy on near-term quantum simulators, with potential applications in quantum chemistry and condensed matter physics.

ESCI ; EI

英语

第一

2-s2.0-85183576545

Scopus

1.Shenzhen Institute for Quantum Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,China
2.International Quantum Academy,Shenzhen,Guangdong,China
3.Guangdong Provincial Key Laboratory of Quantum Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,China
4.Institute of Fundamental and Frontier Sciences,University of Electronic Science and Technology of China,Chengdu,China
5.Department of Physics,Southern University of Science and Technology,Shenzhen,Guangdong,China
6.Key Laboratory of Quantum Physics and Photonic Quantum Information,Ministry of Education,University of Electronic Science and Technology of China,Chengdu,China
7.Beijing Academy of Quantum Information Sciences,Beijing,China

Han，Zhikun,Lyu，Chufan,Zhou，Yuxuan,et al. Multilevel variational spectroscopy using a programmable quantum simulator[J]. Physical Review Research,2024,6(1).

Han，Zhikun.,Lyu，Chufan.,Zhou，Yuxuan.,Yuan，Jiahao.,Chu，Ji.,...&Yu，Dapeng.(2024).Multilevel variational spectroscopy using a programmable quantum simulator.Physical Review Research,6(1).

Han，Zhikun,et al."Multilevel variational spectroscopy using a programmable quantum simulator".Physical Review Research 6.1(2024).