# Discontinuous switching of position of two coexisting phases

## TL;DR

This paper explores how concentration gradients can induce a discontinuous positional switch of a condensed phase in a ternary mixture, revealing a novel phase transition with potential biological and microfluidic applications.

## Contribution

It introduces a mean field model demonstrating a first order phase transition causing abrupt phase position changes due to concentration gradients.

## Key findings

- Discontinuous switching of phase position observed
- First order phase transition identified
- Implications for biological cell organization and microfluidics

## Abstract

Here we investigate how the positions of a condensed phase can be controlled by using concentration gradients of a regulator that influences phase separation. We consider a mean field model of a ternary mixture where a concentration gradient of a regulator is imposed by an external potential. We show that novel first order phase transition exists at which the position of the condensed phase switches in a discontinuous manner. This mechanism could have implications for the spatial organization of biological cells and provides a control mechanism for droplets in microfluidic systems.