The dynamics of wave packets carrying a spatiotemporal vortex in the spatial fractional system is still an open problem.The difficulty stems from the fact that the fractional Laplacian derivative is essentially a nonl...The dynamics of wave packets carrying a spatiotemporal vortex in the spatial fractional system is still an open problem.The difficulty stems from the fact that the fractional Laplacian derivative is essentially a nonlocal operator,and the vortex is space-time coupled.Here,we investigate the transmission of spatiotemporal vortices in the spatial fractional wave equation(FWE)and demonstrate the effects of linewidth,vortex topological charge,and linear chirp modulation on the transmission of Bessel-type spatiotemporal vortex pulses(BSTVPs).Under narrowband conditions,we find that the propagation of BSTVP in the FWE can be seen as the coherent superposition of two linearly shifted half-BSTVPs and can reveal orbital angular momentum backflow for the half-BSTVP.Our analysis can be extended to other spatiotemporal vortex pulses.展开更多
The first intermolecular electrophilic dearomatization of halonaphthols with benzyl/allyl bromides is described. Halonaphthols are used as carbon-nucleophiles in dearomatization to form three-dimensional cyclic enones...The first intermolecular electrophilic dearomatization of halonaphthols with benzyl/allyl bromides is described. Halonaphthols are used as carbon-nucleophiles in dearomatization to form three-dimensional cyclic enones with excellent chemoselectivity, in which etherification of phenolic hydroxyl group could be restrained well by using cesium carbonate as the base. A wide range of cyclic enones is directly prepared from various substituted benzyl/allyl bromides and halonaphthols. Mechanistic investigations suggest a direct S_(N)2 reaction pathway.展开更多
基金National Key Research and Development Program of China(2022YFC2808203)National Natural Science Foundation of China(11474254,11804298).
文摘The dynamics of wave packets carrying a spatiotemporal vortex in the spatial fractional system is still an open problem.The difficulty stems from the fact that the fractional Laplacian derivative is essentially a nonlocal operator,and the vortex is space-time coupled.Here,we investigate the transmission of spatiotemporal vortices in the spatial fractional wave equation(FWE)and demonstrate the effects of linewidth,vortex topological charge,and linear chirp modulation on the transmission of Bessel-type spatiotemporal vortex pulses(BSTVPs).Under narrowband conditions,we find that the propagation of BSTVP in the FWE can be seen as the coherent superposition of two linearly shifted half-BSTVPs and can reveal orbital angular momentum backflow for the half-BSTVP.Our analysis can be extended to other spatiotemporal vortex pulses.
基金The National Natural Science Foundation of China(Nos.21901203,22171225,21925108)the Education Department of Shaanxi Province(No.20JK0934)are acknowledged for financial support.
文摘The first intermolecular electrophilic dearomatization of halonaphthols with benzyl/allyl bromides is described. Halonaphthols are used as carbon-nucleophiles in dearomatization to form three-dimensional cyclic enones with excellent chemoselectivity, in which etherification of phenolic hydroxyl group could be restrained well by using cesium carbonate as the base. A wide range of cyclic enones is directly prepared from various substituted benzyl/allyl bromides and halonaphthols. Mechanistic investigations suggest a direct S_(N)2 reaction pathway.
