Rheology and Dynamics of Active Matter Systems

Active matter is a non-equilibrium branch of matter which is inspired by the self-propulsion and organization of biological systems such as flocks of birds and bacterial colonies.  We use confocal microscopy and dynamic light scattering to analyze the 3D microstructure and 2D dynamics of active colloidal suspensions.  We are also interested in the effect of particle shape on their self-propulsive dynamics.  In addition, we also study the rheological properties of colloidal gels embedded with active matter.  The active motion we produce results from asymmetric particles and environments, such as platinum coated polystyrene spheres and binary colloids, activated either by electric fields or a chemical fuel.  Studying active particles has implications for enhanced mixing and rheological property control in industrial applications such as in foods, ceramics, pharmaceuticals and consumer products. 

Related Publications:

  1. Saud, K. T. and Solomon, M. J., “Microdynamics of active particles in defect-rich colloidal crystals“, Journal of Colloid and Interface Science 641, 950-960 (2023).
  2. Saud, K.T., Ganesan, M. and Solomon, M.J., “Yield stress behavior of colloidal gels with embedded active particles“, Journal of Rheology, 65, 225 – 239 (2021).
  3. Szakasits, M.E., Saud, K., Mao, X. and M.J. Solomon, “Rheological implications of embedded active matter in colloidal gels,” Soft Matter, 15, 8012 – 8021 (2019). 
  4. Shemi, O. and M.J. Solomon, “Self-propulsion and active motion of Janus ellipsoids,” J. Phys. Chem. B122(44) 10247-10255 (2018).
  5. Solomon, M.J., “Tools and Functions of Reconfigurable Colloidal Assembly,” Langmuir 34 11205-11219 (2018).
  6. Szakasits, M.E., W. Zhang, and M.J. Solomon, “Dynamics of fractal cluster gels with embedded active colloids,” Physical Review Letters 119, 58001 (2017).

Contact Current Graduate Student:

  • Chih-Mei Young