Polarization structuring of focused field through polarization-only modulation of incident beam

Abstract

We proposed a method of polarization shaping in the focal region with the polarization modulation of incident light. By using an iterative optimization based on a vectorial diffraction calculation with the help of the fast Fourier transform, we can tailor the polarization structure in the focal plane. This provides a novel way to control the vectorial feature of the focal volume with the help of polarization tailoring, which is different from the method using wavefront shaping. The capability of polarization-only modulation on the incident light is demonstrated by optical experiments.

Light field shaping by tailoring both phase and polarization

“…It should be noted that such space-variant (phase and polarization) beams can be generated by our experimental setup. The focal field of a monochromatic light beam passing through an aplanatic lens is calculated by the vectorial diffraction integral that can be written in terms of a Fourier transform (FT) [20][21][22]. For the sake of simplicity, we restricted our attention to the paraxial focusing in which the longitudinal component of the focal field can be omitted.…”

“…Microscopic optics can greatly benefit from the polarization engineering of light beams in this way [11][12][13], and consequently, there is a growing interest in not only adjusting the overall intensity distribution, but also in manipulating the polarization state distribution in the focal volume [14][15][16][17][18][19]. In a previous paper, we reported on the use of polarization-only modulation of incident beams to implement focus shaping [20]. The study had demonstrated the functionality of polarization manipulation.…”

Reconfigurable beams with arbitrary polarization and shape distributions at a given plane

“…While early studies mainly dealt with spatially homogeneous polarization states, in recent years interest in arbitrary spatially-variant polarized beams (ASPBs) has increased significantly due to their special properties compared to homogeneously polarized beams, which can thereby enhance the functionality of optical systems. Nevertheless, the generation of ASPBs can be a difficult task; while static techniques do not allow dynamic encoding of ASPB patterns [2][3][4][5], a solution can be found using spatial light modulators (SLMs) which can be considered as reconfigurable phase retarder devices controlled by computer [6][7][8][9][10][11][12][13][14][15][16].…”

On the physical realizability of highly focused electromagnetic field distributions

“…Since the electric field distribution in the focal plane depends on the complex amplitude and spatial polarization of the beam at the entrance pupil, the incident field has to be conveniently designed [1][2][3][4][5][6][7][8][9][10][11]. In this Letter, we analyze the feasibility of physically implementing an arbitrary three-dimensional vectorial distribution in the focal area.…”