Light-beam shifts accompanied by propagation between two media show potential in applications such as optical sensing,optical communication,and optical computing.However,existing work tends to focus on the static resp...Light-beam shifts accompanied by propagation between two media show potential in applications such as optical sensing,optical communication,and optical computing.However,existing work tends to focus on the static response of the device,i.e.,the beam shift when the structural parameters and incident conditions are fixed.Here,we analyze the dynamics of beam shifting via photonic crystal slabs under refractive index variation.On the one hand,we investigate the trend of cross-polarized phase gradient under small changes in refractive index.Simulation results show that the direction of the beam shift can change by more than 50°for a refractive index change of only 0.06.On the other hand,we study the interaction of incident light with the far-field polarizations of bound states in the continuum in the presence of a refractive index jump in the phase-change material.In this case,simulation results show that the large change in the Pancharatnam-Berry phase gradient causes the beam to move widely,with a change in beam direction of 61.30°and a change in beam displacement of 15μm.Furthermore,all displacement amounts are comparable to the radius of the incident beam(~8μm).Our work provides a new perspective on the study of beam shifts,which can advance practical applications of beam shift in sensing,intelligent detecting,and beam control.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62405176 and 62175009)the Natural Science Foundation of Shanghai(No.24ZR1435000)+3 种基金the Open Project Program of SJTU Pinghu Institute of Intelligent Optoelectronics(No.2022SP10E202)the Science and Technology on Sonar Laboratory(No.6142109KF212207)the Shanghai Jiao Tong University 2030 Initiative(No.WH510363001-13)the Research Fund of Shanghai Jiao Tong University Explore X。
文摘Light-beam shifts accompanied by propagation between two media show potential in applications such as optical sensing,optical communication,and optical computing.However,existing work tends to focus on the static response of the device,i.e.,the beam shift when the structural parameters and incident conditions are fixed.Here,we analyze the dynamics of beam shifting via photonic crystal slabs under refractive index variation.On the one hand,we investigate the trend of cross-polarized phase gradient under small changes in refractive index.Simulation results show that the direction of the beam shift can change by more than 50°for a refractive index change of only 0.06.On the other hand,we study the interaction of incident light with the far-field polarizations of bound states in the continuum in the presence of a refractive index jump in the phase-change material.In this case,simulation results show that the large change in the Pancharatnam-Berry phase gradient causes the beam to move widely,with a change in beam direction of 61.30°and a change in beam displacement of 15μm.Furthermore,all displacement amounts are comparable to the radius of the incident beam(~8μm).Our work provides a new perspective on the study of beam shifts,which can advance practical applications of beam shift in sensing,intelligent detecting,and beam control.
