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Dynamics of photoexcited states in one-dimensional dimerized Mott insulators

Nobuya Maeshima·Kenji Yonemitsu
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Abstract

Dynamical properties of photoexcited states are theoretically studied in a one-dimensional Mott insulator dimerized by the spin-Peierls instability. Numerical calculations combined with a perturbative analysis have revealed that the lowest photoexcited state without nearest-neighbor interaction corresponds to an interdimer charge transfer excitation that belongs to dispersive excitations. This excited state destabilizes the dimerized phase, leading to a photoinduced inverse spin-Peierls transition. We discuss the purely electronic origin of midgap states that are observed in a latest photoexcitation experiment of an organic spin-Peierls compound, K-TCNQ (potassium-tetracyanoquinodimethane).

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Nobuya Maeshima, Kenji Yonemitsu. 2006-09-08. Dynamics of photoexcited states in one-dimensional dimerized Mott insulators. https://doi.org/10.1103/physrevb.74.155105

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