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arXiv · 2512.17697

Digital-Analog Quantum Computing with Qudits

Alatz Alvarez-Ahedo·Mikel Garcia de Andoin·Mikel Sanz
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Abstract

Digital-analog quantum computing with two-level systems is a computational paradigm that combines an analog Hamiltonian with single-qubit gates to achieve universality. We extend this framework to $d$-level systems by conjugating an analog Hamiltonian block with single-qudit gates drawn from the Weyl-Heisenberg basis, which provides a natural set of operations for qudit architectures. More specifically, we propose a protocol to simulate arbitrary two-body Hamiltonians with at most $O(d^4 n^2)$ analog blocks. The power of this approach is illustrated by the simulation of many-body qudit spin Hamiltonians including magnetic quadrupolar terms.

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Alatz Alvarez-Ahedo, Mikel Garcia de Andoin, Mikel Sanz. 2025-12-19. Digital-Analog Quantum Computing with Qudits. https://arxiv.org/abs/2512.17697

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