@article {Gradient_phase_transition, title = {Switching Droplet Positions by Concentration Gradients}, year = {Submitted}, abstract = {Here we investigate how droplet position can be controlled using concentration profiles 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 that controls droplet position in a discontinuous manner. Such a droplet switch in concentration gradients could be relevant for the spatial organization of biological cells and provides a control mechanism for droplets in microfluidic systems.}, url = {https://arxiv.org/abs/1704.07276.pdf}, author = {Kr{\"u}ger, Samuel and Weber, Christoph A. and Sommer, Jens-Uwe and J{\"u}licher, Frank} }