Optofluidic light routing via analytically configuring streamlines of micro-flow

TL;DR

This paper introduces a novel analytically designed streamline tracing method in optofluidics to manipulate light paths with high tunability, verified through experiments matching theoretical predictions.

Contribution

The paper presents a new streamline tracing-based transformation optofluidics method that allows analytical design of light paths in microfluidic systems, enhancing tunability over traditional transformation optics.

Findings

Light paths match theoretical predictions.

Adjusting flow rates and source-sink positions tunes light paths.

High tunability demonstrated in experiments.

Abstract

Transformation optics (TO) is a new method to design metamaterials that can manipulate electromagnetic fields. Inspired by the traditional TO techniques which is mostly based on the solid metamaterials with a limited range of tunability, a novel streamline tracing-based transformation optofluidics (STTOF) method is proposed to manipulate the light path by analytically designating the light-carrying streamlines of the flow in a two-dimensional circular bounded domain. A dipole flow model is built to analytically calculate the streamlines of the flow field inside the domain which allocates the optical/fluidic source and sink pairs at arbitrary positions. Liquid core/liquid cladding (L2) configuration is used in the experiment to trace the light via a specific streamline. Experimental results verify that the light paths agree well with the theoretical predictions, and demonstrate that a good range of tunability can be achieved by adjusting the flow rates and the source-sink positions of optical/fluidic source and sink pairs.