The topological properties of the spatial coherence function are investigated rigorously. The phase singular structures （coherence vortices） of coherence function can be naturally deduced from the topological curren...The topological properties of the spatial coherence function are investigated rigorously. The phase singular structures （coherence vortices） of coherence function can be naturally deduced from the topological current, which is an abstract mathematical object studied previously. We find that coherence vortices are characterized by the Hopf index and Brouwer degree in topology. The coherence flux quantization and the linking of the closed coherence vortices are also studied from the topological properties of the spatial coherence function.展开更多
Solutions to a piezoelectric half-plane with a fixed conductorsurface electrode subjected to two generalized singularities (linedislocation and/or lien force and free charge) are presented.Coublomb forces acting on th...Solutions to a piezoelectric half-plane with a fixed conductorsurface electrode subjected to two generalized singularities (linedislocation and/or lien force and free charge) are presented.Coublomb forces acting on the singularities due to the boundarypolarization changes of medium and the induction charg- es ofconductor electrode are analyzed in detail. The interaction betweenthe two singularities is also analyzed numerically. Results show thatCoulomb forces will become important as the free change approachesthe boundary or two singularities move closely.展开更多
基金Support by the National Natural Science Foundation of China, and Cuiying Programme of Lanzhou University. The authors would like to thank Xin-Hui Zhang, Dong-Hui Xu, and Ran Li for helpful discussions.
文摘The topological properties of the spatial coherence function are investigated rigorously. The phase singular structures （coherence vortices） of coherence function can be naturally deduced from the topological current, which is an abstract mathematical object studied previously. We find that coherence vortices are characterized by the Hopf index and Brouwer degree in topology. The coherence flux quantization and the linking of the closed coherence vortices are also studied from the topological properties of the spatial coherence function.
基金the National Natural Science Foundation of China (No.10172036).
文摘Solutions to a piezoelectric half-plane with a fixed conductorsurface electrode subjected to two generalized singularities (linedislocation and/or lien force and free charge) are presented.Coublomb forces acting on the singularities due to the boundarypolarization changes of medium and the induction charg- es ofconductor electrode are analyzed in detail. The interaction betweenthe two singularities is also analyzed numerically. Results show thatCoulomb forces will become important as the free change approachesthe boundary or two singularities move closely.
