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arXiv · 2108.07500

Building ground states of Hubbard model by time-ordered bound-pair injection

K. L. Zhang·Z. Song
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Abstract

According to energy band theory, ground states of a normal conductor and insulator can be obtained by filling electrons individually into energy levels, without any restrictions. It fails when the electron-electron correlation is taken into account. In this work, we investigate the dynamic process of building ground states of a Hubbard model. It is based on time-ordered quantum quenches for unidirectional hopping across a central and an auxiliary Hubbard model. We find that there exists a set of optimal parameters (chemical potentials and pair binding energy) for the auxiliary system, which takes the role of electron-pair reservoir. The exceptional point dynamics in non-Hermitian quantum mechanics allows the perfect transfer of electron pair from the reservoir to the central system, obtaining its ground states at different fillings. The dynamics of time-ordered pair-filling not only provides a method for correlated quantum state engineering, but also reveals the feature of the ground state in an alternative way.

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K. L. Zhang, Z. Song. 2021-12-29. Building ground states of Hubbard model by time-ordered bound-pair injection. https://doi.org/10.1103/physrevb.104.245140

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