Self-trapping transition for nonlinear impurities embedded in a Cayley tree

Bikash C. Gupta; Sang Bub Lee

doi:10.1103/physrevb.63.144302

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Self-trapping transition for nonlinear impurities embedded in a Cayley tree

Bikash C. Gupta·Sang Bub Lee

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Abstract

The self-trapping transition due to a single and a dimer nonlinear impurity embedded in a Cayley tree is studied. In particular, the effect of a perfectly nonlinear Cayley tree is considered. A sharp self-trapping transition is observed in each case. It is also observed that the transition is much sharper compared to the case of one-dimensional lattices. For each system, the critical values of $χ$ for the self-trapping transitions are found to obey a power-law behavior as a function of the connectivity $K$ of the Cayley tree.

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Bikash C. Gupta, Sang Bub Lee. 2001-05-22. Self-trapping transition for nonlinear impurities embedded in a Cayley tree. https://doi.org/10.1103/physrevb.63.144302

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