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arXiv · 2405.14466

Ultra-cold atoms quantum tunneling through single and double optical barriers

Roy Eid·Alfred Hammond·Lucas Lavoine·Thomas Bourdel
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Abstract

We realize textbook experiments on Bose-Einstein condensate tunnelling through thin repulsive potential barriers. In particular, we demonstrate atom tunnelling though a single optical barrier in the quantum scattering regime where the De Broglie wavelength of the atoms is larger than the barrier width. Such a beam splitter can be used for atom interferometry and we study the case of two barriers creating an atomic Fabry-P{\'e}rot cavity. Technically, the velocity of the atoms is reduced thanks to the use of a 39K Bose-Einstein condensate with no interactions. The potential barriers are created optically and their width is tunable thanks to the use of a digital micro-mirror device. In addition, our scattering experiments enable in-situ characterization of the optical aberrations of the barrier optical system.

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Roy Eid, Alfred Hammond, Lucas Lavoine, Thomas Bourdel. 2024-05-23. Ultra-cold atoms quantum tunneling through single and double optical barriers. https://arxiv.org/abs/2405.14466

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