Anomalous suppression of photo-induced in-gap weight in the optical conductivity of a two-leg Hubbard ladder

Abstract

Photoinduced nonequilibrium states in the Mott insulators reflect the fundamental nature of competition between itinerancy and localization of the charge degrees of freedom. The spin degrees of freedom will also contribute to the competition in a different manner depending on lattice geometry. We investigate pulse-excited optical responses of a half-filled two-leg Hubbard ladder and compare them with those of a one-dimensional extended Hubbard chain. Calculating the time-dependent optical conductivity, we find that strong mono-cycle pulse inducing quantum tunneling gives rise to anomalous suppression of photo-induced in-gap weight, leading to negative weight. This is in contrast to finite positive weight in the Hubbard chain. The origin of this anomalous behavior in the two-leg ladder is attributed to photoinduced localized exciton that reflects strong spin-singlet dimer correlation in the ground state.

6 pages, 4 figures, to appear in Phys. Rev. B

References in corpus (4)

• Excitons in the One-Dimensional Hubbard Model: a Real-Time Study
• Photoinduced in-gap excitations in the one-dimensional extended Hubbard model
• Density-matrix renormalization group study of optical conductivity of the Mott insulator for two-dimensional clusters
• Glassy dynamics of the one-dimensional Mott insulator excited by a strong terahertz pulse

Cited by in corpus (6)

• Extracting Nonlinear Dynamical Response Functions from Time Evolution
• Keldysh crossover in one-dimensional Mott insulators
• Optical absorption activated by an ultrashort half-cycle pulse in metallic and superconducting states of the Hubbard model
• Charge creation via quantum tunneling in one-dimensional Mott insulators: A numerical study of the extended Hubbard model
• Tangent equations of motion for nonlinear response functions
• Low-energy photoexcitations inside the Mott gap in doped Hubbard and t-J ladders