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Impurity Energy Level Within The Haldane Gap

Wei Wang·Shaojin Qin·Zhong-Yi Lu·Lu Yu·Zhaobin Su
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Abstract

An impurity bond $J{'}$ in a periodic 1D antiferromagnetic, spin 1 chain with exchange $J$ is considered. Using the numerical density matrix renormalization group method, we find an impurity energy level in the Haldane gap, corresponding to a bound state near the impurity bond. When $J{'} J$. The impurity level appears only when the deviation $dev=(J{'}-J)/J{'}$ is greater than $B_{c}$, which is near 0.3 in our calculation.

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Wei Wang, Shaojin Qin, Zhong-Yi Lu, Lu Yu, Zhaobin Su. 1995-09-06. Impurity Energy Level Within The Haldane Gap. https://doi.org/10.1103/physrevb.53.40

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