aiqbench analysis
This study demonstrates that qudit-based encodings offer superior accuracy for simulating molecular vibrational dynamics compared to standard qubit methods, even when accounting for current noise levels. The findings suggest that leveraging higher-dimensional quantum states could be a promising pathway for future quantum chemistry applications as hardware matures.
Simulation of vibrational dynamics using qubits and qudits
arXiv:2605.12866v2 Announce Type: replace Abstract: We investigate the quantum computing of the vibrational dynamics of CO$_2$ and H$_2$O by constructing the vibrational third-order anharmonic Hamiltonian in qubit and qudit form by two types of qubit encodings (binary and direct) and a qudit encoding. We simulate the time-dependent vibrational population transfer using the three different encodings, including the effect of noise and find that the qudit encoding leads to the most accurate results both for CO$_2$ and H$_2$O because of the small number of terms in the qudit Hamiltonian as long as the same values of the entangling gate error rates are adopted. Although the entangling gate errors of current qudit quantum computers are approximately one order of magnitude larger than the entangling gate errors of current qubit quantum computers, our results suggest that the simulation of vibrational dynamics is a promising application for future qudit quantum computers.
Abstract:We investigate the quantum computing of the vibrational dynamics of CO$_2$ and H$_2$O by constructing the vibrational third-order anharmonic Hamiltonian in qubit and qudit form by two types of qubit encodings (binary and direct) and a qudit encoding. We simulate the time-dependent vibrational population transfer using the three different encodings, including the effect of noise and find that the qudit encoding leads to the most accurate results both for CO$_2$ and H$_2$O because of the small number of terms in the qudit Hamiltonian as long as the same values of the entangling gate error rates are adopted. Although the entangling gate errors of current qudit quantum computers are approximately one order of magnitude larger than the entangling gate errors of current qubit quantum computers, our results suggest that the simulation of vibrational dynamics is a promising application for future qudit quantum computers.
17 pages; 8 figures. This version is close to the published version
arXiv:2605.12866 [quant-ph]
(or arXiv:2605.12866v2 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2605.12866 Focus to learn more arXiv-issued DOI via DataCite
Phys. Rev. A 114, 022816 (2026)
https://doi.org/10.1103/q69k-y623 Focus to learn more DOI(s) linking to related resources
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Full text under the publisher's open licence · 259 words
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