Monotonous manipulation of atomic density in an isovolumetric focused-beam trap

TL;DR

This paper demonstrates a method to monotonously control atomic density in a focused-beam trap of rubidium-85 by adjusting laser intensities, enabling precise loading of a specific number of atoms.

Contribution

It introduces a novel asymmetric focused-beam trap where atomic density is controlled solely by trap laser intensity, allowing precise atom number loading.

Findings

Atomic cloud volume varies with trap laser intensity.

Density can be monotonously manipulated from zero to maximum.

Scheme enables loading of exactly 1-6 atoms in the trap.

Abstract

We present an asymmetric focused-beam trap of rubidium-85 atoms where the cloud volume only varied with the trap laser intensity. By repumping on F=2 to F'=2 D2 transition, the Stokes Raman scattering has strongly affected the population ratio in the two hyperfine ground states. With the volume and trap number simultaneously and separately controlled, we have shown that the cloud density can be monotonously manipulated from zero to the maximum value limited by the cooling power. By solely varying the intensity of repump laser, the scheme for precision loading of exact 1-6 atoms in the FORT, which is beyond the practical loading limit of the blue-detuned light-assisted collision, is described.