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arXiv · 2512.11619

Tight bound for the total time in digital-analog quantum computation

Mikel Garcia-de-Andoin·Mikel Sanz
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Abstract

Digital-analog quantum computing (DAQC) is a universal computational paradigm that combines the evolution under an entangling Hamiltonian with the application of single-qubit gates. Since any unitary operation can be decomposed into a sequence of evolutions generated by two-body Hamiltonians, DAQC is inherently well-suited for realizing such operations. Suboptimal upper bounds for the total time required to perform these evolutions have been previously proposed. Here, we improve these limits by providing a tight bound for this crucial parameter, which shows a linear dependence with the number of couplings. This result enables a precise estimation of the time resources needed for quantum simulations and quantum algorithms implemented within the DAQC framework, facilitating a rigorous comparison with other approaches.

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Mikel Garcia-de-Andoin, Mikel Sanz. 2025-12-12. Tight bound for the total time in digital-analog quantum computation. https://doi.org/10.1103/pkz9-vjkh

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