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Low-Lying Electronic Excitations and Nonlinear Optic Properties of Polymers via Symmetrized Density Matrix Renormalization Group Method

S. Ramasesha·Swapan K. Pati·H. R. Krishnamurthy·Z. Shuai·J. L. Bredas
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Abstract

A symmetrized Density Matrix Renormalization Group procedure together with the correction vector approach is shown to be highly accurate for obtaining dynamic linear and third order polarizabilities of one-dimensional Hubbard and $U-V$ models. The $U-V$ model is seen to show characteristically different third harmonic generation response in the CDW and SDW phases. This can be rationalized from the excitation spectrum of the systems.

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S. Ramasesha, Swapan K. Pati, H. R. Krishnamurthy, Z. Shuai, J. L. Bredas. 1996-09-17. Low-Lying Electronic Excitations and Nonlinear Optic Properties of Polymers via Symmetrized Density Matrix Renormalization Group Method. https://arxiv.org/abs/cond-mat/9609164

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