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  • Site-selective doublon-holon dynamics in a pumped one-dimensional Hubbard superlattice with staggered Coulomb interactions
Title: Site-selective doublon-holon dynamics in a pumped one-dimensional Hubbard superlattice with staggered Coulomb interactions
Doublon-holon dynamics is investigated in a pumped one-dimensional Hubbard model with a staggered on-site Coulomb interaction at half-filling. When the system parameters are set to be in the Mott-insulating regime the equilibrium sublattice density of states exhibits several characteristic peaks, corresponding to the lower and upper Hubbard bands as well as hybridization bands. We study the linear absorption spectrum and find two main peaks characterizing the photon frequencies which excite the ground state to an excited state. For a system driven by a laser pulse with general intensity and frequency, both the energy absorption and the doublon-holon dynamics exhibit distinct behaviors as a function of laser amplitude and frequency. Single-photon processes are observed at low laser intensity where the energy is absorbed for resonant laser frequencies. For strong laser intensity multiphoton-induced dynamics are observed in the system that are confirmed by an evaluation of the Loschmidt amplitude. The contribution of multiphoton processes to site-resolved double occupancy is also characterized by the generalized Loschmidt amplitude. The site-resolved doublon-holon dynamics are observed in both the one and multiphoton processes and the site-resolved behavior is explained within a quasiparticle picture. Our study suggests strategies to optically engineer the doublon-holon dynamics in one-dimensional strongly correlated many-body systems.  more » « less
Award ID(s):
2114825
PAR ID:
10554359
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Physical Society, PRB
Date Published:
Journal Name:
Physical Review B
Volume:
109
Issue:
19
ISSN:
2469-9950
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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