RESEARCH FIELD

Soft Matter Physics

Soft matter physics investigates materials that are neither simple fluids nor crystalline solids — systems whose mechanical properties are intermediate and that exhibit rich phase behaviour and dynamics. Canonical soft matter systems include polymer solutions and melts, liquid crystals exploited in display technology, colloidal suspensions, gels and hydrogels, emulsions, foams, and biological matter including lipid membranes, cytoskeleton, and cell tissues. A unifying concept is that soft matter structures are set by entropy and interaction energies comparable to thermal energy kBT, producing phenomena such as self-assembly, phase separation, gelation, and viscoelastic flow. Active matter — systems of self-propelled agents from bacteria to cytoskeletal filaments driven by molecular motors — extends soft matter into the non-equilibrium realm, exhibiting spontaneous flow and collective motion. The field underpins polymer processing, food science, cosmetics, display technology, and biomaterials engineering. Key techniques include dynamic and static light scattering, neutron scattering, rheometry, and particle tracking microrheology. Funding comes from national science foundations, the polymer and materials industries, and biophysics programmes.