Membrane heterogeneity-driven dynamics of multicomponent vesicles in shear flow

Despite its significance in biology and materials science, the dynamics of multicomponent vesicles under shear flow remains poorly understood because of its nonlinear and strongly coupled nature, especially regarding the role of membrane heterogeneity in driving non-equilibrium behaviour. Here we present a thermodynamically consistent phase-field model, which is validated against experiments, for the quantitative investigation of the dynamics. While prior research has primarily focused on viscosity or bending rigidity contrasts, we demonstrate that surface tension heterogeneity can also trigger swinging and tumbling in vesicles under shear. Additionally, our systematic phase diagram reveals three previously unreported dynamical regimes arising from the interplay between bending rigidity heterogeneity and shear flow. Overall, our model provides a robust framework for understanding multicomponent vesicle dynamics, with findings offering new physical insights and design principles for tuneable vesicle-based carriers.