Generation of a hollow dark spherical spot by 4pi focusing of a radially polarized Laguerre-Gaussian beam

Abstract

The properties of the focal spot for 4pi focusing with radially polarized first-order Laguerre-Gaussian beams are calculated. It is shown that a focal spot that has an extremely sharp dark region at the center and an almost-perfect spherical symmetry can be achieved. When such a hollow dark spherical spot is used in 4pi fluorescence depletion microscopy, an axial FWHM spot size of approximately 39 nm and a transverse FWHM spot size of approximately 64 nm can be achieved simultaneously in a practical system.

Analysis of the axial distribution of a tightly focused beam with different polarizations

“…Если z велико, то интенсивность для выражений (15), (16) Более компактные оценки без зависимости от диапазона изменения z можно получить, когда в ин-тегралах (14) отрезок интегрирования небольшой, т.е. кольцевая апертура не слишком широкая.…”

Generation of compact radially polarized beam at 850 nm in vertical-cavity surface-emitting laser via plasmonic modulation

“…6 The optical bubble created by radially polarized beam with diffractive optical element pupil plane modulation can be applied in microscopy techniques. 7 Radially polarized beams can also produce better plasmonic focusing with axially symmetric plasmonic structures. 8 Driven by the application demands of the radially polarized beam, various active and passive methods have been developed to generate radially polarized beam since 1972, 9 including an axial intracavity birefringence component 10 or a conical Brewster prism 11 utilized in Nd:yttrium aluminum garnet lasers.…”

Generation of multiple focal spot and focal hole segments using phase modulated cylindrically polarized annular multi-Gaussian beam

“…Growing interest in the generation of three-dimensional (3D) optical beams that are dark regions in space surrounded by light are driven by wide ranging applications including dark optical traps for atoms (Zhan and Leger 2002;Friedman et al 2002), manipulation, guiding and binding of microparticles and biological cells (Cizmar et al 2010), erase beams for super-resolution fluorescence microscopy (Watanabe et al 2003), etc. Over the past years, a variety of techniques have been proposed for generating such optical bottle beams for applications in optical tweezers and atom traps (GarciaSucerquia et al 2004;Chen and Zhan 2006;Bokor and Davidson 2006;Ahluwalia et al 2006;Arlt and Padgett 2000;Ahluwalia et al 2004;Yelin et al 2004;Pu et al 2005). However, stable trapping of a single particle is expected if we can make the bottles small enough and comparable to the particle size.…”