Colloidal transport through optical tweezer arrays

TL;DR

This study investigates how colloidal particles move through optical tweezer arrays, confirming that particle size relative to trap spacing determines whether particles become trapped or pass through.

Contribution

The paper experimentally verifies the theoretical prediction that particle size and trap spacing ratio control colloidal transport states in optical tweezer arrays.

Findings

Particles become kinetically locked or escape depending on size-to-spacing ratio

Experimental results confirm theoretical predictions

Transport behavior can be controlled by adjusting particle size or trap spacing

Abstract

Viscously damped particles driven past an evenly spaced array of potential energy wells or barriers may become kinetically locked in to the array, or else may escape from the array. The transition between locked-in and free-running states has been predicted to depend sensitively on the ratio between the particles' size and the separation between wells. This prediction is confirmed by measurements on monodisperse colloidal spheres driven through arrays of holographic optical traps.