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arXiv · 2410.08268

Disorder-Free Localization for Benchmarking Quantum Computers

Jad C. Halimeh·Uliana E. Khodaeva·Dmitry L. Kovrizhin·Roderich Moessner·Johannes Knolle
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Abstract

Disorder-free localization (DFL) is a phenomenon as striking as it appears to be simple: a translationally invariant state evolving under a disorder-free Hamiltonian failing to thermalize. It is predicted to occur in a number of quantum systems exhibiting emergent or native \emph{local} symmetries. These include models of lattice gauge theories and, perhaps most simply, some two-component spin chains. Though well-established analytically for special soluble examples, numerical studies of generic systems have proven difficult. Moreover, the required local symmetries are a challenge for any experimental realization. Here, we show how a canonical model of DFL can be efficiently implemented on gate-based quantum computers, which relies on our efficient encoding of three-qubit gates. We show that the simultaneous observation of the absence of correlation spreading and tunable entanglement growth to a volume law provides an ideal testbed for benchmarking the capabilities of quantum computers. In particular, the availability of a soluble limit allows for a rigorous prediction of emergent localization length scales and tunable time scales for the volume law entanglement growth, which are ideal for testing capabilities of scalable quantum computers.

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Jad C. Halimeh, Uliana E. Khodaeva, Dmitry L. Kovrizhin, Roderich Moessner, Johannes Knolle. 2024-10-10. Disorder-Free Localization for Benchmarking Quantum Computers. https://arxiv.org/abs/2410.08268

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