Fractional vortex beams exhibit a higher degree of modulation dimensions than conventional vortices,thus inheriting superior anti-turbulent transmission properties through the incorporation of additional coherence mod...Fractional vortex beams exhibit a higher degree of modulation dimensions than conventional vortices,thus inheriting superior anti-turbulent transmission properties through the incorporation of additional coherence modulation.However,aliasing the mixed modes induced by coherence degradation makes the quantitative measurement of the topological charge in fractional vortex beams challenging.In this study,a coherence phase spectrum was introduced,and experimental demonstrations to quantitatively determine the fractional topological charge of partially coherent fractional vortex beams were performed.By leveraging the four-dimensional measurement of a partially coherent light field,the source coherence function was inversely reconstructed,and fractional topological charges were determined with high precision by extracting the phase spectrum of the coherence function.Laguerre–Gaussian,elliptical Gaussian,and plane-wave-fraction vortex beams with various degrees of coherence were used to demonstrate measurement precision.The proposed method is applicable to X-rays and electron vortices.It has potential applications in optical encryption,high-capacity optical communication,and quantum entanglement.展开更多
A general model for creating an optical vortex using a variable-width Fermat spiral slit(FSS)mask was developed.The generated optical vortex demonstrates much better quality than those produced by slits with a uniform...A general model for creating an optical vortex using a variable-width Fermat spiral slit(FSS)mask was developed.The generated optical vortex demonstrates much better quality than those produced by slits with a uniform width.The depth of focus was nearly doubled,which can be explained by discretizing the gradual-width FSS.To demonstrate the generation robustness,the slits were printed on a transparent slide,and an output vortex beam with greater than 98%intensity purity was obtained.With the high quality and simplicity of this vortex generation method,its analysis and generation scheme are expected to be extended to generation of plasmonic vortices and short-wavelength light sources such as X-rays and electron beams.Generation of highquality optical vortex beams at an almost negligible cost will make investigation much more accessible.展开更多
基金National Key Research and Development Program of China(2019YFA0705000,2022YFA1404800)National Natural Science Foundation of China(11974218,12174280,12192254,12204340,92050202,92250304)+2 种基金China Postdoctoral Science Foundation(2022M722325)Priority Academic Program Development of Jiangsu Higher Education InstitutionsKey Laboratory of Modern Optical Technologies of Jiangsu Province(KJS2138)。
文摘Fractional vortex beams exhibit a higher degree of modulation dimensions than conventional vortices,thus inheriting superior anti-turbulent transmission properties through the incorporation of additional coherence modulation.However,aliasing the mixed modes induced by coherence degradation makes the quantitative measurement of the topological charge in fractional vortex beams challenging.In this study,a coherence phase spectrum was introduced,and experimental demonstrations to quantitatively determine the fractional topological charge of partially coherent fractional vortex beams were performed.By leveraging the four-dimensional measurement of a partially coherent light field,the source coherence function was inversely reconstructed,and fractional topological charges were determined with high precision by extracting the phase spectrum of the coherence function.Laguerre–Gaussian,elliptical Gaussian,and plane-wave-fraction vortex beams with various degrees of coherence were used to demonstrate measurement precision.The proposed method is applicable to X-rays and electron vortices.It has potential applications in optical encryption,high-capacity optical communication,and quantum entanglement.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1404800,and 2019YFA0705000)the National Natural Science Foundation of China(Grant Nos.12204340,12174280,12192254,11974218,92250304,and 92050202)+4 种基金the China Postdoctoral Science Foundation(Grant No.2022M722325)the Priority Academic Program Development of Jiangsu Higher Education Institutions,Tang ScholarLocal Science and Technology Development Project of the Central Government(Grant No.YDZX20203700001766)the Key Lab of Modern Optical Technologies of Jiangsu Province(Grant No.KJS2138)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX22_3183)。
文摘A general model for creating an optical vortex using a variable-width Fermat spiral slit(FSS)mask was developed.The generated optical vortex demonstrates much better quality than those produced by slits with a uniform width.The depth of focus was nearly doubled,which can be explained by discretizing the gradual-width FSS.To demonstrate the generation robustness,the slits were printed on a transparent slide,and an output vortex beam with greater than 98%intensity purity was obtained.With the high quality and simplicity of this vortex generation method,its analysis and generation scheme are expected to be extended to generation of plasmonic vortices and short-wavelength light sources such as X-rays and electron beams.Generation of highquality optical vortex beams at an almost negligible cost will make investigation much more accessible.
