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Optical Susceptibilities of Polymers: Current-Current versus Dipole-Dipole Correlation

Minzhong Xu·Xin Sun
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Abstract

The static current operator leads to definitional zero frequency divergence and unphysical results in studying nonlinear optical susceptibilities of polymers. A well-defined dipole-dipole correlation is superior to the complicated current-current correlation to solve this problem. As illustrative examples, optical susceptibilities under both SSH and TLM models of trans-(CH)_x are studied. New analytical results are obtained. The reasons of previous improper results are analyzed.

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Minzhong Xu, Xin Sun. 1999-05-27. Optical Susceptibilities of Polymers: Current-Current versus Dipole-Dipole Correlation. https://doi.org/10.1016/s0375-9601(99)00288-1

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