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The anomalous tunneling of Bose-condensate excitations

Yu. Kagan·D. L. Kovrizhin·L. A. Maksimov
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Abstract

We discuss the tunneling of phonon excitations across a potential barrier separating two condensate bulks. It is shown that the strong barrier proves to be transparent for the excitations at low energy $ε$. Moreover, the transmission is reduced with increasing $ε$ in contrast to the standard dependence. This anomalous behavior is due to an existence of the quasiresonance interaction. The origin of this interaction is a result of the formation of the special well determined by the density distribution of condensate in the vicinity of a high barrier.

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Yu. Kagan, D. L. Kovrizhin, L. A. Maksimov. 2002-10-15. The anomalous tunneling of Bose-condensate excitations. https://arxiv.org/abs/cond-mat/0210329

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