УДК: 535.42

Sharp focusing of laser beams in anisotropic uniaxial crystals

Khonina, S.N., Zoteeva, O.V., Kharitonov, S.I.

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Хонина С.Н., Зотеева О.В., Харитонов С.И. Острая фокусировка лазерных пучков в анизотропных одноосных кристаллах // Оптический журнал. 2015. Т. 82. № 4. С. 23–31.

Khonina S.N., Zoteeva O.V., Kharitonov S.I. Sharp focusing of laser beams in anisotropic uniaxial crystals [in Russian] // Opticheskii Zhurnal. 2015. V. 82. № 4. P. 23–31.

For citation (Journal of Optical Technology):

S. N. Khonina, S. I. Kharitonov, and O. V. Zoteeva, "Sharp focusing of laser beams in anisotropic uniaxial crystals," Journal of Optical Technology. 82(4), 212-219 (2015). https://doi.org/10.1364/JOT.82.000212

Abstract:

This paper discusses the sharp focusing of homogeneously polarized laser beams in a uniaxial crystal. It is shown analytically and numerically that, when homogeneously polarized radiation is sharply focused along the axis of a crystal, two foci are formed, corresponding to the ordinary and extraordinary rays. The introduction of a vortex phase into the incident beam results in the formation of zero intensity at the center of the focus of the ordinary rays and a longitudinal electric-field component at the center of the focus of the extraordinary rays. The contribution of the longitudinal component is greater, the sharper the focusing. With circular polarization, larger amplification of the longitudinal component is observed, and its intensity becomes comparable with that of the transverse components. This results in the formation of a focus of the extraordinary rays with a flat vertex.

Keywords:

sharp focusing, uniaxial crystal, vortex laser beam, longitudinal electric-field component

Acknowledgements:

This work was carried out with the financial support of the Russian Foundation for Basic Research (RFFI Grants 13-07-00266, 13-07-9700r_povolzh’e_a, “My first grant,” and 14-01-31401 mol_a) and the Ministry of Education and Science of the Russian Federation.

OCIS codes: 050.1970, 050.4865, 260.1440

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