Topological Defects in Nematic Liquid Crystals: Laboratory of Fundamental Physics

摘要

Topological defects (TDs) appear in all branches of physics due to the simplicityof generic mechanisms: The necessary condition for their existence is spontaneoussymmetry breaking in a relevant physical field. Nematic liquid crystals(NLCs) represent an ideal testbed for their study and they can display point, line,textures, and in favorable conditions also wall defects. TDs in NLCs can berelatively easily created, controlled, and experimentally observed. This enables adetailed and controlled analysis of their physical properties, leading to thecross-fertilization of knowledge among different areas of physics, includingcondensed matter, particle physics, and cosmology. Furthermore, TDs in NLCscould be exploited in diverse applications. Herein, some salient features ofmost common TDs in NLCs, their generic mechanisms, their importance forfundamental science, and possible applications based on them are illustrated.