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arXiv · 2606.05297

Continuous-variable ADAPT-VQE for bosonic lattice models

Dimitrios Athanasakos·Gloria Tejedor-García·Jack Y. Araz·Mafalda Ramôa·Bharath Sambasivam·Sophia E. Economou·Felix Ringer
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Abstract

We present a continuous-variable adaptive variational quantum eigensolver (CV-ADAPT-VQE). As concrete examples, we consider the ground-state preparation for (i) the Bose-Hubbard model and (ii) the bosonic Kitaev chain, including its extension with an on-site Kerr interaction. The former conserves the total boson number, while the latter conserves global parity. We construct symmetry-preserving operator pools tailored to each case and show, using GPU-based classical simulations, that CV-ADAPT-VQE results in significantly shallower circuits compared to Hamiltonian-based VQE approaches. Our results point toward direct applications in quantum simulations of condensed-matter systems, quantum chemistry, and high-energy physics.

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Dimitrios Athanasakos, Gloria Tejedor-García, Jack Y. Araz, Mafalda Ramôa, Bharath Sambasivam, Sophia E. Economou, Felix Ringer. 2026-06-03. Continuous-variable ADAPT-VQE for bosonic lattice models. https://arxiv.org/abs/2606.05297

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