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.