Dynamically creating asymmetrical potential wells for nanoparticle manipulation

TL;DR

This paper introduces a method to dynamically create and control asymmetrical potential wells using holograms, enhancing the manipulation capabilities of optical tweezers for nanoparticles.

Contribution

It presents a novel approach for generating and controlling asymmetrical potential wells with holograms, enabling improved nanoparticle manipulation.

Findings

Demonstrated dynamic control of potential well depth, stiffness, and location.

Achieved controllable transport of nanoparticles with adjustable paths and velocities.

Expanded the capabilities of optical tweezers for nanoparticle manipulation.

Abstract

Optical tweezers, which are powerful tools for trapping and manipulating particles, have been widely used in many areas. However, their potential wells are typically symmetrical, which limit their capability of optical trapping and manipulation. Herein, we report an approach for dynamically creating asymmetrical potential wells, by employing variable phase gradient profiles generated by holograms. Its depth, stiffness and location of potential wells can be dynamically controlled. Moreover, the controllable transport of nanoparticle is experimentally demonstrated, which reveals that it exhibits excellent manipulation performance. Importantly, its motion path, step distance and velocity can be easily manipulated by changing its holograms, which is highly desirable in controllable transport of nanoparticles. This study offers a new tool for optical manipulation, which could largely expand the capability of conventional optical tweezers.