Investigation of polarization effects for high-numerical-aperture first-order Laguerre-Gaussian beams by 2D scanning with a single fluorescent microbead

Abstract

The focal intensity distribution of strongly focused (NA=0.9) first order Laguerre-Gaussian doughnut beams is investigated experimentally for three different polarizations: linear, and left-handed circular and right-handed circular. The investigations are done by 2-dimensional scanning the focal plane with of a 100nm diameter fluorescent microbead, and measuring the fluorescence signal. The results are shown to be in excellent agreement with theoretical predictions, and demonstrate the superiority of one of the circular polarizations to achieve a sharp dark central spot.

Development of Super-Resolution Microscopy—Application of Laguerre-Gaussian Beam to Microscopy—

“…To generate a focused 1st-order of LG beam with a zero intensity center hole, here, we introduce polarization control for the incident erase beam [8]. Now, let us consider another beam with a different incident polarization component, shown by the green arrow, i.e.…”

Tight Focusing of Partially Coherent Vortex Beams

“…Polarization distribution of tightly focused optical beams has drawn considerable interest in recent years and recent advances in the field of nanophotonics have contributed much to the rapid progress of the field [1][2][3][4][5][6][7]. Tightly focused structure of the optical field possesses three-dimensional structure, and x-, y-, and z-polarization components are involved in shaping the focal structure [1].…”

“…Input polarization of the beam becomes a dominating factor apart from complex amplitude in shaping the focused structure. For example, optical vortex produces doughnut structure in the low NA focusing, whereas existence of the doughnut in tightly focused structure of vortex beam depends on its topological charge as well as on its polarization distribution [6,[8][9][10][11][12].…”

Quantitative force mapping of an optical vortex trap

“…6,14 We simulated the three-dimensional distribution of the strongly focused optical field through the glass-water interface by applying Maxwell's boundary conditions and the vectorial Debye integral. To create the optical force map, we employed a multidipole approach.…”

“…14,16,17 Here, we follow Richards and Wolf and apply Maxwell's boundary conditions to calculate the electric field passing through the glass-water interface as the beam is focused into the water. The strongly focused electric fields of the x-polarized Lagueree-Gaussian ͑LG 0 1 ͒ vortex beam can be expressed as [18][19][20] ͑see Ref.…”