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arXiv · 2408.03801

Hamiltonian learning for 300 trapped ion qubits with long-range couplings

S. -A. Guo·Y. -K. Wu·J. Ye·L. Zhang·Y. Wang·W. -Q. Lian·R. Yao·Y. -L. Xu·C. Zhang·Y. -Z. Xu·B. -X. Qi·P. -Y. Hou·L. He·Z. -C. Zhou·L. -M. Duan
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Abstract

Quantum simulators with hundreds of qubits and engineerable Hamiltonians have the potential to explore quantum many-body models that are intractable for classical computers. However, learning the simulated Hamiltonian, a prerequisite for any applications of a quantum simulator, remains an outstanding challenge due to the fast increasing time cost with the qubit number and the lack of high-fidelity universal gate operations in the noisy intermediate-scale quantum era. Here we demonstrate the Hamiltonian learning of a two-dimensional ion trap quantum simulator with 300 qubits. We employ global manipulations and single-qubit-resolved state detection to efficiently learn the all-to-all-coupled Ising model Hamiltonian, with the required quantum resources scaling at most linearly with the qubit number. Our work paves the way for wide applications of large-scale ion trap quantum simulators.

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S. -A. Guo, Y. -K. Wu, J. Ye, L. Zhang, Y. Wang, W. -Q. Lian, R. Yao, Y. -L. Xu, C. Zhang, Y. -Z. Xu, B. -X. Qi, P. -Y. Hou, L. He, Z. -C. Zhou, L. -M. Duan. 2024-08-07. Hamiltonian learning for 300 trapped ion qubits with long-range couplings. https://doi.org/10.1126/sciadv.adt4713

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