Shunsuke Yabunaka

Self-propelled motion of a fluid droplet under chemical reaction

We study self-propelled dynamics of a droplet due to a Marangoni effect and chemical reactions in a binary fluid with a dilute third component of chemical product which affects the interfacial energy of a droplet. The equation for the migration velocity of the center of mass of a droplet is derived in the limit of an infinitesimally thin interface. We found that there is a bifurcation from a motionless state to a propagating state of droplet by changing the strength of the Marangoni effect.

Surprises in

We find that the multicritical fixed point structure of the O(N) models is much more complicated than widely believed. In particular, we find new nonperturbative fixed points in three dimensions (d=3) as well as at N=∞. These fixed points come together with an intricate double-valued structure when they are considered as functions of d and N. Many features found for the O(N) models are shared by the O(N)⊗O(2) models relevant to frustrated magnetic systems.

O(N)

We investigate phase separation of near-critical binary mixtures between parallel symmetric walls in the strong adsorption regime. We take into account the renormalization effect due to the critical fluctuations using the recent local functional theory [Okamoto and Onuki, J. Chem. Phys. 136, 114704 (2012)]. In statics, a van der Waals loop is obtained in the relation between the average order parameter

Models: Nonperturbative Fixed Points, Large

\ensuremath{\langle}\ensuremath{\psi}\ensuremath{\rangle}

N

in the film and the chemical potential when the temperature

Limits, and Multicriticality

T

Phase separation in a binary mixture confined between symmetric parallel plates: Capillary condensation transition near the bulk critical point

is lower than the film critical temperature

Emergence of epithelial cell density waves

{T}_{c}^{\mathrm{ca}}

Collision between chemically-driven self-propelled drops

(in the case of an upper critical solution temperature). In dynamics, we lower

Cell growth, division, and death in cohesive tissues: A thermodynamic approach

T