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Nonlinear Krönig-Penney model

Wei-Dong Li·A. smerzi
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Abstract

We study the nonlinear Schrödinger equation with a periodic delta-function potential. This realizes a nonlinear Krönig-Penney model, with physical applications in the context of trapped Bose-Einstein condensate alkaly gases and in the transmission of signals in optical fibers. We find analytical solutions of zero-current Bloch states. Such wave-functions have the same periodicity of the potential, and, in the linear limit, reduce to the Bloch functions of the Krönig-Penney model. We also find new classes of solutions having a periodicity different from that of the external potential. We calculate the chemical potential of such states and compare it with the linear excitation spectrum.

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Wei-Dong Li, A. smerzi. 2004-06-30. Nonlinear Krönig-Penney model. https://doi.org/10.1103/physreve.70.016605

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