Disorder-induced neutral solitons in degenerate ground state polymers

Marc Thilo Figge; Maxim V. Mostovoy; Jasper Knoester

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arXiv · cond-mat/9811240

Disorder-induced neutral solitons in degenerate ground state polymers

Marc Thilo Figge·Maxim V. Mostovoy·Jasper Knoester

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Abstract

In this letter, we study the effects of weak off-diagonal disorder on conjugated polymers with a doubly degenerate ground-state. We find that disorder induces a finite density of neutral solitons in the lattice dimerization of a polymer chain. Interchain interactions result in a linear potential between the solitons and, if sufficiently strong, bind them into pairs resulting in an exponential suppression of the soliton density. As neutral solitons carry spin 1/2, they contribute to the polymer's magnetic properties. We calculate the magnetic susceptibility and suggest measurements of the magnetic susceptibility in {\it trans}-polyacetylene at low temperatures.

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Marc Thilo Figge, Maxim V. Mostovoy, Jasper Knoester. 1998-11-17. Disorder-induced neutral solitons in degenerate ground state polymers. https://arxiv.org/abs/cond-mat/9811240

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