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arXiv · 1009.2713

An elementary exposition of the Efimov Effect

Rajat K. Bhaduri·Arindam Chatterjee·Brandon P. van Zyl
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Abstract

Two particles that are just shy of binding may develop an infinite number of shallow bound states when a third particle is added. This counter intuitive quantum mechanical result was first predicted by V. Efimov for identical bosons interacting with a short-range pair-wise potential. The so-called Efimov effect persists even for non-identical particles, provided at least two of the three bonds are almost bound. The Efimov effect has recently been verified experimentally using ultra-cold atoms. In this article, we explain the origin of this effect using only elementary quantum mechanics, and summarize the experimental evidence for the Efimov effect. A new, simple derivation for the number of Efimov states is given in the Appendix.

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Rajat K. Bhaduri, Arindam Chatterjee, Brandon P. van Zyl. 2010-09-14. An elementary exposition of the Efimov Effect. https://doi.org/10.1119/1.3533428

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