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arXiv · 2010.09792

Hollow Bessel beams for guiding atoms between vacuum chambers: A proposal and efficiency study

Dalila Rivero·Vinicius S. de Angelis·Camila Beli·Michelle Moreno·Leonardo Ambrosio·Philippe W. Courteille
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Abstract

We explore a scheme for guiding cold atoms through a hollow Bessel beam generated by a single axicon and a lens from a 2D magneto-optical trap toward a science chamber. We compare the Bessel beam profiles measured along the optical axis to a numerical propagation of the beam's wavefront, and we show how it is affected by diffraction during the passage through a long narrow funnel serving as a differential pumping tube between the chambers. We derive an approximate analytic expression for the intensity distribution of the Bessel beam and the dipolar optical force acting on the atoms. By a Monte-Carlo simulation based on a stochastic Runge-Kutta algorithm of the motion of atoms initially prepared at a given temperature we show that a considerable enhancement of the transfer efficiency can be expected in the presence of a sufficiently intense Bessel beam.

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Dalila Rivero, Vinicius S. de Angelis, Camila Beli, Michelle Moreno, Leonardo Ambrosio, Philippe W. Courteille. 2020-10-19. Hollow Bessel beams for guiding atoms between vacuum chambers: A proposal and efficiency study. https://doi.org/10.1364/josab.395200

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