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arXiv · 2307.00966

Digital-Analog Quantum Computation with Arbitrary Two-Body Hamiltonians

Mikel Garcia-de-Andoin·Álvaro Saiz·Pedro Pérez-Fernández·Lucas Lamata·Izaskun Oregi·Mikel Sanz
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Abstract

Digital-analog quantum computing is a computational paradigm which employs an analog Hamiltonian resource together with single-qubit gates to reach universality. Here, we design a new scheme which employs an arbitrary two-body source Hamiltonian, extending the experimental applicability of this computational paradigm to most quantum platforms. We show that the simulation of an arbitrary two-body target Hamiltonian of $n$ qubits requires $\mathcal{O}(n^2)$ analog blocks with guaranteed positive times, providing a polynomial advantage compared to the previous scheme. Additionally, we propose a classical strategy which combines a Bayesian optimization with a gradient descent method, improving the performance by $\sim55\%$ for small systems measured in the Frobenius norm.

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Mikel Garcia-de-Andoin, Álvaro Saiz, Pedro Pérez-Fernández, Lucas Lamata, Izaskun Oregi, Mikel Sanz. 2023-07-03. Digital-Analog Quantum Computation with Arbitrary Two-Body Hamiltonians. https://doi.org/10.1103/physrevresearch.6.013280

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