Controlling terahertz(THz)polarization with high stability and tunability is essential for achieving further progress in ultrafast spectroscopy,structured-light manipulation,and quantum information processing.Here,we ...Controlling terahertz(THz)polarization with high stability and tunability is essential for achieving further progress in ultrafast spectroscopy,structured-light manipulation,and quantum information processing.Here,we propose a magnetized plasma platform for dynamic THz polarization control by exploiting the intrinsic birefringence between extraordinary and ordinary modes.We identify a strong-magnetization,zero-group-velocity-mismatch regime where the two modes share matched group velocities while retaining finite phase birefringence,enabling robust,phase-stable spin angular momentum control.By tuning the plasma length and magnetic field,we realize programmable phase retardation and demonstrate universal single-qubit gates through parameterized unitary operations.Full-wave particle-in-cell simulations validate high-fidelity polarization transformations across the Poincarésphere and demonstrate the potential for generating structured vector beams under spatially varying magnetic fields.The platform offers ultrafast response,resilience to extreme THz intensities,and in situ tunability,positioning magnetized plasmas as a versatile and damage-resilient medium for next-generation THz polarization control and structured-wave applications.展开更多
Planar optical elements incorporating space-varying Pancharatnam-Berry phase have revolutionized the manipulation of light fields by enabling continuous control over amplitude,phase,and polarization.While previous res...Planar optical elements incorporating space-varying Pancharatnam-Berry phase have revolutionized the manipulation of light fields by enabling continuous control over amplitude,phase,and polarization.While previous research focusing on linear functionalities using apolar liquid crystals(LCs)has attracted much attention,extending this concept to the nonlinear regime offers unprecedented opportunities for advanced optical processing.Here,we demonstrate the reconfigurable nonlinear Pancharatnam-Berry LC diffractive optics in photopatterned ion-doped ferroelectric nematics.By customizing the spatial phase distribution of efficient second-harmonic excitation,we accomplish programmable beam steering of various optical states towards predefined diffraction directions.Experimental results reveal continuous evolution of diffraction orders,intensity distributions,and polarization states under electrically varying splay conditions,consistent with our theoretical predictions.This work opens new avenues for designing reconfigurable nonlinear beam shaping and steering devices with potential applications in advanced optical and quantum information processing.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 12175058 and 11921006)the National Grand Instrument Project (No. 2019YFF01014402)the Beijing Distinguished Young Scientist Program and National Grand Instrument Project No. SQ2019YFF01014400
文摘Controlling terahertz(THz)polarization with high stability and tunability is essential for achieving further progress in ultrafast spectroscopy,structured-light manipulation,and quantum information processing.Here,we propose a magnetized plasma platform for dynamic THz polarization control by exploiting the intrinsic birefringence between extraordinary and ordinary modes.We identify a strong-magnetization,zero-group-velocity-mismatch regime where the two modes share matched group velocities while retaining finite phase birefringence,enabling robust,phase-stable spin angular momentum control.By tuning the plasma length and magnetic field,we realize programmable phase retardation and demonstrate universal single-qubit gates through parameterized unitary operations.Full-wave particle-in-cell simulations validate high-fidelity polarization transformations across the Poincarésphere and demonstrate the potential for generating structured vector beams under spatially varying magnetic fields.The platform offers ultrafast response,resilience to extreme THz intensities,and in situ tunability,positioning magnetized plasmas as a versatile and damage-resilient medium for next-generation THz polarization control and structured-wave applications.
基金supported by the National Key Research and Development Program of China(Nos.2022YFA1405000(Y.-Q.L.,L.-L.M.)and 2021YFA1202000(L.-L.M.))National Natural Science Foundation of China(Nos.T2488302(Y.-Q.L.),62375119(L.-L.M.),and 62305157(W.C.))+1 种基金Natural Science Foundation of Jiangsu Province(Nos.BK20243067(Y.-Q.L.)and BK20232040(L.-L.M.))Fundamental Research Funds for the Central Universities(Nos.2024300360 and 2025300215(L.-L.M.)).
文摘Planar optical elements incorporating space-varying Pancharatnam-Berry phase have revolutionized the manipulation of light fields by enabling continuous control over amplitude,phase,and polarization.While previous research focusing on linear functionalities using apolar liquid crystals(LCs)has attracted much attention,extending this concept to the nonlinear regime offers unprecedented opportunities for advanced optical processing.Here,we demonstrate the reconfigurable nonlinear Pancharatnam-Berry LC diffractive optics in photopatterned ion-doped ferroelectric nematics.By customizing the spatial phase distribution of efficient second-harmonic excitation,we accomplish programmable beam steering of various optical states towards predefined diffraction directions.Experimental results reveal continuous evolution of diffraction orders,intensity distributions,and polarization states under electrically varying splay conditions,consistent with our theoretical predictions.This work opens new avenues for designing reconfigurable nonlinear beam shaping and steering devices with potential applications in advanced optical and quantum information processing.
