Topological photonics provides a strategy that makes light transmission immune to structural-defects-induced backward scattering.Leveraging this,topological negative refraction enables robust,reflectionless light defl...Topological photonics provides a strategy that makes light transmission immune to structural-defects-induced backward scattering.Leveraging this,topological negative refraction enables robust,reflectionless light deflection,but directly controlling the refraction direction remains challenging.We demonstrate continuously tunable topological negative refraction at the interface between a one-way waveguide state and a free-space beam,overcoming the limitations of fixed refraction angles in conventional systems.The key insight is the ability to adjust the wavevector of the incident one-way waveguide state.Through manipulating the Bloch wavevector of the waveguide states in momentum space,we achieve a transition from negative to positive refraction.The unidirectional nature of these states prevents backscattering from defects,ensuring immunity to imperfections.As a prototypical demonstration,we achieve dynamic steering of refraction beams from-38°to+12°through active magnetic bias control.Our findings provide an exotic pathway for photon manipulation and a promising route toward topological photonics applications.展开更多
The elimination of transverse wavevectors during the propagation of electromagnetic waves is highly desirable because this would have a wide range of applications in probing,imaging,and communication.In this research,...The elimination of transverse wavevectors during the propagation of electromagnetic waves is highly desirable because this would have a wide range of applications in probing,imaging,and communication.In this research,we propose and experimentally demonstrate a simple method to suppress transverse wavevectors by using coherent wave combinations.Using theoretical analysis and numerical simulation,we show that transverse wavevectors can be greatly suppressed during propagation.For further verification,we perform experiments with light waves to realize coherently combined beams;our experimental results are in good agreement with the simulated results.More importantly,we generate pin-like optical beams using this method,and pin-like optical beams exhibit superior propagation behavior over conventional Gaussian beams in turbulent fluids.展开更多
基金National Natural Science Foundation of China(12434016,12474380)Science and Technology Project of Guangdong(2020B010190001)+1 种基金National Key Research and Development Program of China(2023YFA1406900)Natural Science Foundation of Guangdong Province(2025A1515010714)。
文摘Topological photonics provides a strategy that makes light transmission immune to structural-defects-induced backward scattering.Leveraging this,topological negative refraction enables robust,reflectionless light deflection,but directly controlling the refraction direction remains challenging.We demonstrate continuously tunable topological negative refraction at the interface between a one-way waveguide state and a free-space beam,overcoming the limitations of fixed refraction angles in conventional systems.The key insight is the ability to adjust the wavevector of the incident one-way waveguide state.Through manipulating the Bloch wavevector of the waveguide states in momentum space,we achieve a transition from negative to positive refraction.The unidirectional nature of these states prevents backscattering from defects,ensuring immunity to imperfections.As a prototypical demonstration,we achieve dynamic steering of refraction beams from-38°to+12°through active magnetic bias control.Our findings provide an exotic pathway for photon manipulation and a promising route toward topological photonics applications.
文摘The elimination of transverse wavevectors during the propagation of electromagnetic waves is highly desirable because this would have a wide range of applications in probing,imaging,and communication.In this research,we propose and experimentally demonstrate a simple method to suppress transverse wavevectors by using coherent wave combinations.Using theoretical analysis and numerical simulation,we show that transverse wavevectors can be greatly suppressed during propagation.For further verification,we perform experiments with light waves to realize coherently combined beams;our experimental results are in good agreement with the simulated results.More importantly,we generate pin-like optical beams using this method,and pin-like optical beams exhibit superior propagation behavior over conventional Gaussian beams in turbulent fluids.
