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arXiv · 2407.07843

Spin/Phonon Dynamics in Single Molecular Magnets: II. spin/phonon entanglemen

Nosheen Younas·Yu Zhang·Andrei Piryatinski·Eric R Bittner
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Abstract

We introduce a new quantum embedding method to explore spin-phonon interactions in molecular magnets. This technique consolidates various spin/phonon couplings into a limited number of collective degrees of freedom, allowing for a fully quantum mechanical treatment. By precisely factorizing the entire system into "system" and "bath" sub-ensembles, our approach simplifies a previously intractable problem, making it solvable on modest-scale computers. We demonstrate the effectiveness of this method by studying the spin relaxation and dephasing times of the single-molecule qubit \ce{VOPc(OH)8}, which features a lone unpaired electron on the central vanadium atom. By using this mode projection method, we are able to perform numerical exact quantum dynamical calculation on this system which allows us to follow the flow of quantum information from the single spin qubit into the projected phonon degrees of freedom. Our results demonstrate both the utility of the method and suggest how one can engineer the environment as to further optimize the quantum properties of a qubit system.

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Nosheen Younas, Yu Zhang, Andrei Piryatinski, Eric R Bittner. 2024-07-10. Spin/Phonon Dynamics in Single Molecular Magnets: II. spin/phonon entanglemen. https://arxiv.org/abs/2407.07843

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