| 초록 |
Translation-rotation decoupling is one of hallmarks of glassy dynamics; translation is often faster than expected from the viscosity of liquids unlike rotation. The decoupling relates closely to spatially heterogeneous dynamics where dynamically correlated regions emerge about molecular dimensions. In this talk, we present the dependence of the decoupling on tracer shape in two-dimensional (2D) colloids introducing three shapes of tracers (diamond, distorted diamond and square) representative regarding local 6-fold media structure. Near the liquid-hexatic phase transition, the translation-rotation decoupling occurs for all tracers regardless of their shapes, but its trends are different qualitatively for different shape. Based on our simulation results in 2D colloids, we discuss the structural motif of dynamic heterogeneity such as locally favorable structures in general glass-formers. |
