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arXiv · 2402.15371

Non-adiabatic quantum dynamics with fermionic subspace-expansion algorithms on quantum computers

Anthony Gandon·Alberto Baiardi·Pauline Ollitrault·Ivano Tavernelli
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Abstract

We introduce a novel computational framework for excited-states molecular quantum dynamics simulations driven by quantum computing-based electronic-structure calculations. This framework leverages the fewest-switches surface-hopping method for simulating the nuclear dynamics, and calculates the required excited-state transition properties with different flavors of the quantum subspace expansion and quantum equation-of-motion algorithms. We apply our method to simulate the collision reaction between a hydrogen atom and a hydrogen molecule. For this system, we critically compare the accuracy and efficiency of different quantum subspace expansion and equation-of-motion algorithms and show that only methods that can capture both weak and strong electron correlation effects can properly describe the non-adiabatic effects that tune the reactive event.

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Anthony Gandon, Alberto Baiardi, Pauline Ollitrault, Ivano Tavernelli. 2024-02-23. Non-adiabatic quantum dynamics with fermionic subspace-expansion algorithms on quantum computers. https://arxiv.org/abs/2402.15371

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