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arXiv · 2310.15091

Digital quantum simulation of lattice fermion theories with local encoding

Marco Ballarin·Giovanni Cataldi·Giuseppe Magnifico·Daniel Jaschke·Marco Di Liberto·Ilaria Siloi·Simone Montangero·Pietro Silvi
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Abstract

We numerically analyze the feasibility of a platform-neutral, general strategy to perform quantum simulations of fermionic lattice field theories under open boundary conditions. The digital quantum simulator requires solely one- and two-qubit gates and is scalable since integrating each Hamiltonian term requires a finite (non-scaling) cost. The exact local fermion encoding we adopt relies on auxiliary $\mathbb{Z}_2$ lattice gauge fields by adding a pure gauge Hamiltonian term akin to the Toric Code. By numerically emulating the quantum simulator real-time dynamics, we observe a timescale separation for spin- and charge-excitations in a spin-$\frac{1}{2}$ Hubbard ladder in the $t-J$ model limit.

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Marco Ballarin, Giovanni Cataldi, Giuseppe Magnifico, Daniel Jaschke, Marco Di Liberto, Ilaria Siloi, Simone Montangero, Pietro Silvi. 2023-10-23. Digital quantum simulation of lattice fermion theories with local encoding. https://doi.org/10.22331/q-2024-09-04-1460

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