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arXiv · 2407.20957

Shortcuts for Adiabatic and Variational Algorithms in Molecular Simulation

Julián Ferreiro-Vélez·Iñaki Iriarte-Zendoia·Yue Ban·Xi Chen
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Abstract

Quantum algorithms are prominent in the pursuit of achieving quantum advantage in various computational tasks. However, addressing challenges, such as limited qubit coherence and high error rate in near-term devices, requires extensive efforts. In this paper, we present a substantial stride in quantum chemistry by integrating shortcuts-to-adiabaticity techniques into adiabatic and variational algorithms for calculating the molecular ground state. Our approach includes the counter-diabatic driving that accelerates adiabatic evolution by mitigating adiabatic errors. Additionally, we introduce the counter-diabatic terms as the adiabatic gauge ansatz for the variational quantum eigensolver, which exhibits favorable convergence properties with a fewer number of parameters, thereby reducing the circuit depth. Our approach achieves comparable accuracy to other established ansatzes, while enhancing the potential for applications in material science, drug discovery, and molecular simulations.

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Julián Ferreiro-Vélez, Iñaki Iriarte-Zendoia, Yue Ban, Xi Chen. 2024-07-30. Shortcuts for Adiabatic and Variational Algorithms in Molecular Simulation. https://arxiv.org/abs/2407.20957

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