Direct Numerical Simulations of Metallodielectric Janus Particles

Metallodielectric Janus particles under external electric fields have quickly become one of the canonical experimental realizations of active matter systems. However, given the complexity of the system, which includes the polarizability of the particles, the electro-hydrodynamic phenomena (e.g., induced-charge electrophoresis), and the particle-fluid coupling, many of the observed single and many-particle properties have not been fully explained. To overcome this, we introduce an extension of the Smoothed Profile Method [1], a direct numerical simulation method for hydrodynamically interacting rigid particles in complex fluids, in order to explicitly incorporate the propulsion mechanism of metallodielectric Janus particles fueled by external electric fields. We use this model to perform 2D and 3D simulations of Janus particles under AC/DC electric fields, in order to study their single and many-particle dynamics, and the dependence on the (frequency-dependent) material properties.

[1] R. Yamamoto, J. J. Molina, Y. Nakayama, Soft Matter 17, 4226-4253 (2021)