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arXiv · 2303.12322

Time-resolved single-particle spectrum of the one-dimensional extended Hubbard model after interaction quenches

Yong-Guang Su·Ruifeng Lu·Hantao Lu·Can Shao
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Abstract

We investigate the non-equilibrium dynamics of the one-dimensional extended Hubbard model after interaction quenches. In strong-coupling regime with large on-site interaction, the ground states of this model with small and large nearest-neighbor interactions are in spin-density-wave and charge-density-wave phases, respectively. Combining twisted boundary conditions with the time-dependent Lanczos method, we obtain snapshots of the time-dependent single-particle spectrum after quenches. We find that for quench within the same phase, the single-particle spectrum becomes close to that of the quenched Hamiltonian immediately after the quench. While for quench across the critical point, the afterward evolution process depends mainly on the distribution of the initial state among the eigenstates of the quenched Hamiltonian. Our finding may serve as a way to detect the phase transition in ultracold atom systems with interactions.

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Yong-Guang Su, Ruifeng Lu, Hantao Lu, Can Shao. 2023-03-22. Time-resolved single-particle spectrum of the one-dimensional extended Hubbard model after interaction quenches. https://doi.org/10.1088/1361-6455%2Facc49b

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