| 초록 |
Two-dimensional (2D) crystalline melting is of particular interest in materials science as their thermodynamic phase transitions can be dimension-dependent. Theoretically, 2D melting is predicted as a two-step phase transition from crystal to hexatic and from hexatic to liquid, but the transition with hexatic phase has not yet been demonstrated in detail experimentally. Previous studies have employed 2D analogs; however, the 2D crystals obtained in a limited area hindered the observation of 2D melting and its characterization. In this talk, I will demonstrate that the melting of a single crystalline monolayer of block copolymer (BCP) spheres enables clear observation of 2D melting transition. We firstly investigated the creation of a 2D crystalline array of BCP spheres over a centimeter-scale area. Then, continuous melting in a 2D crystalline array was induced at various temperatures. Three distinct phases were observed after melting as predicted in the theoretical 2D melting scenario. |
