Localized efficient in-vacuum loading of $\sim$0.1-10 $\mu$m spherical and plate-like particles into optical traps using a pulled glass capillary

TL;DR

This paper introduces a compact, versatile micropipette launcher for precise in-vacuum delivery of nano- and microparticles into various optical traps, achieving high trapping efficiency and broad particle compatibility.

Contribution

The work presents a novel, integrated micropipette launcher compatible with multiple optical trapping setups, enabling efficient in-vacuum particle loading with high precision.

Findings

Achieved trapping efficiency up to 93%.

Successfully trapped diverse particles including silica spheres, nanodiamonds, and hexagonal prisms.

Characterized device performance including peak acceleration and particle emission distribution.

Abstract

We demonstrate a compact piezoelectric-driven micropipette launcher for localized in-vacuum delivery of nano- and microparticles into optical traps. The launcher has been integrated into multiple optical trapping setups, including a single-beam trap, a non-interfering dual beam trap, and a standing-wave dual beam trap, showcasing the versatility and ease of integration of the setup. Using the micropipette launcher, we have successfully trapped silica spheres of $170\text{ nm}$, $300\text{ nm}$, 3 $\mu\text{m}$ diameter, as well as 6 $\mu\text{m}\times$ 0.2 $\mu\text{m}$ $\beta$-NaYF hexagonal prisms and $\sim 100$ nm diameter high-purity nanodiamonds. We characterize the performance of the device including the peak acceleration, angular distribution of emitted particles, and the dependence on vertical displacement between the pipette tip and optical trap. Trapping efficiency as high as 93\% is achieved.