wavefrontengub/localstokes

Code implementation of Photonics Research paper on Local Stokes parameters of a higly focused light beam

Local characterization of the polarization state of three-dimensional electromagnetic fields: An alternative approach

Rosario Martinez-Herrero¹, David Maluenda², Marcos Pérez-Aviñoa², Artur Carnicer², Ignasi Juvells², and Angel Sanz¹

¹Universidad Complutense de Madrid (UCM), Departamento de Óptica, Ciudad Universitaria, 28040, Madrid, Spain

²Universitat de Barcelona (UB), Facultat de Física, Departament de Física aplicada, Martí i Franquès 1, 08028, Barcelona, Spain

Photonics Research, Vol. 11, Issue 7, pp. 1326-1338 (2023)
_{DOI: 10.1364/PRJ.488703 ; Received: 27 Feb 2023 ; Accepted: 17 May 2023 ; Posted: 23 May 2023}

Abstract: A precise knowledge of the polarization state of light is crucial in technologies that involve the generation and application of structured light fields. The implementation of efficient methods aimed at determining and characterizing polarization states and, more importantly, at any spatial location at a low expense is thus mandatory. Here, we introduce a new characterization method, which relies on a rather convenient description of electric fields without neglecting their three-dimensional nature. This method is indeed particularly suitable for highly focused fields, which exhibit important polarization contributions along their propagation direction in the neighborhood of the focal region, i.e., contributions out of the planes transverse to the optical axis, conventionally used to specify the polarization state of these fields. As it is shown, the method allows us to extract information about the three field components at relatively low computational and experimental costs. Furthermore, it also allows to characterize the polarization state of the field in a rather simple manner. To check the feasibility and reliability of the method, we have determined both analytically and experimentally the local polarization states for a series of benchmark input fields with it, finding an excellent agreement between theory and experiment.

Go to the Report.ipynb jupyter notebook to find the implementation and results of this work.

localstokes's Issues

Possible bugs

• Phase in the phases.npz are complex numbers of modulus 1 and its corresponding phase

https://github.com/WavefrontEngUB/stokes3D/blob/f151c6ce5f2b8f6f7c9ae160bc4ddea2ee75a7cd/stokes_simples.py#L79

• The F(Ez) should be made of F(Ex) and F(Ey) -> Replace Ex/Ey with Ax/Ay

https://github.com/WavefrontEngUB/stokes3D/blob/f151c6ce5f2b8f6f7c9ae160bc4ddea2ee75a7cd/stokes_simples.py#L42-L52