Focusing a Vortex Laser Beam with Polarization Conversion
We show that when strongly focusing a linearly polarized optical vortex with the topological charge 2 (or −2) in the near-focus region, there occurs not only a reverse energy flow (where the projection of the Poynting vector is negative) but the right- (or left-) handed circular polarization of ligh...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-10-01
|
| Series: | Photonics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2304-6732/8/11/480 |
| _version_ | 1797508765608574976 |
|---|---|
| author | Victor V. Kotlyar Anton G. Nalimov Sergey S. Stafeev |
| author_facet | Victor V. Kotlyar Anton G. Nalimov Sergey S. Stafeev |
| author_sort | Victor V. Kotlyar |
| collection | DOAJ |
| description | We show that when strongly focusing a linearly polarized optical vortex with the topological charge 2 (or −2) in the near-focus region, there occurs not only a reverse energy flow (where the projection of the Poynting vector is negative) but the right- (or left-) handed circular polarization of light as well. Notably, thanks to spin–orbital conversion, the on-axis polarization vector handedness is the same as that of the transverse energy flow, i.e., anticlockwise (clockwise). An absorbing spherical microparticle centered on the optical axis placed in the focus may be expected to rotate anticlockwise (clockwise) around its axis and its center of masses. We also show that in the case of sharp focusing of light with linear polarization (without an optical vortex) before and after focus, the light has an even number of local regions with left- and right-handed circular (elliptical) polarizations. Theoretical predictions are corroborated by the numerical simulation. |
| first_indexed | 2024-03-10T05:09:31Z |
| format | Article |
| id | doaj.art-fa3c5867636049b985cb834729b5a265 |
| institution | Directory Open Access Journal |
| issn | 2304-6732 |
| language | English |
| last_indexed | 2024-03-10T05:09:31Z |
| publishDate | 2021-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Photonics |
| spelling | doaj.art-fa3c5867636049b985cb834729b5a2652023-11-23T01:01:14ZengMDPI AGPhotonics2304-67322021-10-0181148010.3390/photonics8110480Focusing a Vortex Laser Beam with Polarization ConversionVictor V. Kotlyar0Anton G. Nalimov1Sergey S. Stafeev2Image Processing Systems Institute of RAS—Branch of the FSRC “Crystallography and Photonics” RAS, 151 Molodogvardeyskaya St., 443001 Samara, RussiaImage Processing Systems Institute of RAS—Branch of the FSRC “Crystallography and Photonics” RAS, 151 Molodogvardeyskaya St., 443001 Samara, RussiaImage Processing Systems Institute of RAS—Branch of the FSRC “Crystallography and Photonics” RAS, 151 Molodogvardeyskaya St., 443001 Samara, RussiaWe show that when strongly focusing a linearly polarized optical vortex with the topological charge 2 (or −2) in the near-focus region, there occurs not only a reverse energy flow (where the projection of the Poynting vector is negative) but the right- (or left-) handed circular polarization of light as well. Notably, thanks to spin–orbital conversion, the on-axis polarization vector handedness is the same as that of the transverse energy flow, i.e., anticlockwise (clockwise). An absorbing spherical microparticle centered on the optical axis placed in the focus may be expected to rotate anticlockwise (clockwise) around its axis and its center of masses. We also show that in the case of sharp focusing of light with linear polarization (without an optical vortex) before and after focus, the light has an even number of local regions with left- and right-handed circular (elliptical) polarizations. Theoretical predictions are corroborated by the numerical simulation.https://www.mdpi.com/2304-6732/8/11/480optical vortexpolarization conversionoptical angular momentum |
| spellingShingle | Victor V. Kotlyar Anton G. Nalimov Sergey S. Stafeev Focusing a Vortex Laser Beam with Polarization Conversion Photonics optical vortex polarization conversion optical angular momentum |
| title | Focusing a Vortex Laser Beam with Polarization Conversion |
| title_full | Focusing a Vortex Laser Beam with Polarization Conversion |
| title_fullStr | Focusing a Vortex Laser Beam with Polarization Conversion |
| title_full_unstemmed | Focusing a Vortex Laser Beam with Polarization Conversion |
| title_short | Focusing a Vortex Laser Beam with Polarization Conversion |
| title_sort | focusing a vortex laser beam with polarization conversion |
| topic | optical vortex polarization conversion optical angular momentum |
| url | https://www.mdpi.com/2304-6732/8/11/480 |
| work_keys_str_mv | AT victorvkotlyar focusingavortexlaserbeamwithpolarizationconversion AT antongnalimov focusingavortexlaserbeamwithpolarizationconversion AT sergeysstafeev focusingavortexlaserbeamwithpolarizationconversion |