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Nonlinear optical response and spin-charge separation in one-dimensional Mott insulators

Y. Mizuno·K. Tsutsui·T. Tohyama·S. Maekawa
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Abstract

We theoretically study the nonlinear optical response and photoexcited states of the Mott insulators. The nonlinear optical susceptibility χ^(3) is calculated by using the exact diagonalization technique on small clusters. From the systematic study of the dependence of χ^(3) on dimensionality, we find that the spin-charge separation plays a crucial role in enhancing χ^(3) in the one-dimensional (1D) Mott insulators. Based on this result, we propose a holon-doublon model, which describes the nonlinear response in the 1D Mott insulators. These findings show that the spin-charge separation will become a key concept of optoelectronic devices.

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Y. Mizuno, K. Tsutsui, T. Tohyama, S. Maekawa. 2000-07-08. Nonlinear optical response and spin-charge separation in one-dimensional Mott insulators. https://doi.org/10.1103/physrevb.62.r4769

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