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arXiv · 2402.08969

Systematic many-fermion Hamiltonian input scheme and spectral calculations on quantum computers

Weijie Du·James P. Vary
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Abstract

We present a novel input scheme for general second-quantized Hamiltonians of relativistic or non-relativistic many-fermion systems. This input scheme incorporates the fermionic anticommutation relations, particle number variations, and respects the symmetries of the Hamiltonian. Based on our input scheme, we propose a hybrid quantum-classical framework for spectral calculations on future quantum hardwares. We provide explicit circuit designs and the associated gate cost. We demonstrate our hybrid framework by solving the low-lying spectra of ${^{42}}$Ca and ${^{46}}$Ca. Our input scheme provides new pathways to solving the spectra and dynamics of the relativistic and nonrelativistic many-fermion systems via first-principles approaches.

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Weijie Du, James P. Vary. 2024-02-14. Systematic many-fermion Hamiltonian input scheme and spectral calculations on quantum computers. https://doi.org/10.1016/j.physletb.2025.139548

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