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arXiv · 2205.09557

In-Gap Band Formation in a Periodically Driven Charge Density Wave Insulator

Alexander Osterkorn·Constantin Meyer·Salvatore R. Manmana
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Abstract

Periodically driven quantum many-body systems host unconventional behavior not realized at equilibrium. Here we investigate such a setup for strongly interacting spinless fermions on a chain, which at zero temperature and strong interactions form a charge density wave insulator. Using unbiased numerical matrix product state methods for time-dependent spectral functions, we find that driving of the correlated charge-density wave insulator leads not only to a renormalization of the excitation spectrum as predicted by an effective Floquet Hamiltonian, but also to a cosine-like in-gap feature. This is not obtained for a charge density wave model without interactions. A mean-field treatment provides a partial explanation in terms of doublon excitations. However, the full picture needs to take into account strong correlation effects.

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Alexander Osterkorn, Constantin Meyer, Salvatore R. Manmana. 2022-05-19. In-Gap Band Formation in a Periodically Driven Charge Density Wave Insulator. https://doi.org/10.1038/s42005-023-01346-2

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