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An orbital energy flow and a spin flow at the tight focus
S.S. Stafeev 1,2

1 IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS,
443001, Samara, Russia, Molodogvardeyskaya 151,
2 Samara National Research University, 443086, Samara, Russia, Moskovskoye Shosse 34

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DOI: 10.18287/2412-6179-CO-867

Pages: 520-524.

Full text of article: Russian language.

Abstract:
We have shown that a reverse energy flow (negative projection of the Poynting vector onto the optical axis) at the sharp focus of an optical vortex with topological charge 2 and left-hand circular polarization arises because the axial spin flow has a negative projection onto the optical axis and is greater in magnitude than positive projection onto the optical axis of the orbital energy flow (canonical energy flow). Also, using the Richards-Wolf formulas, it is shown that when focusing a left-handed circularly polarized light, in the region of the on-axis reverse energy flow, the light is right-handed circularly polarized.

Keywords:
orbital energy flow, spin flow, tight focusing, energy backflow, optical vortex.

Citation:
Stafeev SS. An orbital energy flow and a spin flow at the tight focus. Computer Optics 2021; 45(4): 520-524. DOI: 10.18287/2412-6179-CO-867.

Acknowledgements:
This work was supported by the Russian Science Foundation (grant 18-19-00595) in terms of modeling, the Russian Foundation for Basic Research (grant 18-29-20003) in the theoretical part, and the Ministry of Science and Higher Education of the Russian Federation in the framework of works on the State task of the Federal Research Center "Crystallography and Photonics" RAS.

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