High-numerical-aperture and long-working-distance objectives for single-atom experiments

TL;DR

This paper introduces two commercially assembled long-working-distance objective lenses with high numerical apertures suitable for single-atom experiments, offering correction for spherical aberrations and near-diffraction-limited performance across visible and near-infrared wavelengths.

Contribution

The authors present two novel, commercially assembled objective lenses with high NA and long working distances, optimized for single-atom trapping and manipulation.

Findings

Achieved NA of 0.29 and 0.4 with working distances of 34.6 mm and 18.2 mm.

Confirmed optical performance through simulations and imaging tests.

Lenses suitable for trapping and manipulating various atomic species.

Abstract

We present two long-working-distance objective lenses with numerical apertures (NA) of 0.29 and 0.4 for single-atom experiments. The objective lenses are assembled entirely by the commercial on-catalog $\Phi$1'' singlets. Both the objectives are capable to correct the spherical aberrations due to the standard flat vacuum glass windows with various thickness. The working distances of NA$=0.29$ and NA$=0.4$ objectives are 34.6 mm and 18.2 mm, respectively, at the design wavelength of 852 nm with 5-mm thick silica window. In addition, the objectives can also be optimized to work at diffraction limit at single wavelength in the entire visible and near infrared regions by slightly tuning the distance between the first two lenses. The diffraction limited fields of view for NA$=0.29$ and NA$=0.4$ objectives are 0.62 mm and 0.61 mm, and the spatial resolutions are 1.8 $\mu$m and 1.3 $\mu$m at the design wavelength. The performances are simulated by the commercial ray-tracing software and confirmed by imaging the resolution chart and a 1.18 $\mu$m pinhole. The two objectives can be used for trapping and manipulating single atoms of various species.