The intensity distribution in the focal region of a high-NA lens for the incident azimuthally polarized multi Gaussian beam transmitted through a multi belt spiral phase hologram is studied on the basis of the vector ...The intensity distribution in the focal region of a high-NA lens for the incident azimuthally polarized multi Gaussian beam transmitted through a multi belt spiral phase hologram is studied on the basis of the vector diffraction theory. Here we report a new method used to generate a needle of transversely polarized light beam with sub diffraction beam size of 0.366A that propagates without divergence over a long distance of about 22A in free space. We also expect that such a light needle of transversely polarized beam may find its applications in utilizing optical materials or instruments responsive to the transversal field only.展开更多
It is well known that a light spot of sub-wavelength will diverge in all directions. In this letter, A method is presented for generating sub-wavelength （0.44λ） longitudinally polarized beam, which propagates witho...It is well known that a light spot of sub-wavelength will diverge in all directions. In this letter, A method is presented for generating sub-wavelength （0.44λ） longitudinally polarized beam, which propagates without divergence over lengths of about 2λ in free space. This is achieved by a high numerical aperture （NA） lens axicon that utilizes spherical aberration to duplicate the performance of an axicon and to create an extended focal line.展开更多
文摘The intensity distribution in the focal region of a high-NA lens for the incident azimuthally polarized multi Gaussian beam transmitted through a multi belt spiral phase hologram is studied on the basis of the vector diffraction theory. Here we report a new method used to generate a needle of transversely polarized light beam with sub diffraction beam size of 0.366A that propagates without divergence over a long distance of about 22A in free space. We also expect that such a light needle of transversely polarized beam may find its applications in utilizing optical materials or instruments responsive to the transversal field only.
基金the University Research Fellowship offered by Periyar University
文摘It is well known that a light spot of sub-wavelength will diverge in all directions. In this letter, A method is presented for generating sub-wavelength （0.44λ） longitudinally polarized beam, which propagates without divergence over lengths of about 2λ in free space. This is achieved by a high numerical aperture （NA） lens axicon that utilizes spherical aberration to duplicate the performance of an axicon and to create an extended focal line.
