Launch and capture of a single particle in a pulse-laser-assisted dual-beam fiber-optic trap

TL;DR

This paper explores how a pulse laser can assist in launching and capturing microspheres within a dual-beam fiber-optic trap, enhancing control for applications in optomechanics and force sensing.

Contribution

It introduces a method to optimize pulse laser parameters for effective microsphere capture in fiber-optic traps, including derivation of pulse duration and analysis of structural effects.

Findings

Effective capture region identified for launched microspheres.

Optimal pulse duration derived based on detachment energy threshold.

Structural parameters significantly influence launching efficiency.

Abstract

The rapid loading and manipulation of microspheres in optical trap is important for its applications in optomechanics and precision force sensing. We investigate the microsphere behavior under coaction of a dual-beam fiber-optic trap and a pulse laser beam, which reveals a launched microsphere can be effectively captured in a spatial region. A suitable order of pulse duration for launch is derived according to the calculated detachment energy threshold of pulse laser. Furthermore, we illustrate the effect of structural parameters on the launching process, including the spot size of pulse laser, the vertical displacement of beam waist and the initial position of microsphere. Our result will be instructive in the optimal design of the pulse-laser-assisted optical tweezers for controllable loading mechanism of optical trap.