Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing
We introduce and investigate a novel Laguerre-Gaussian (LG) beam, different from the conventional modal LG beams, which conserve the transverse intensity structure (up to scale) on propagation. The proposed beam does not conserve its structure on free space propagation but possesses some interesting...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-09-01
|
| Series: | Photonics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2304-6732/9/10/708 |
| _version_ | 1797470243799433216 |
|---|---|
| author | Victor V. Kotlyar Eugeny G. Abramochkin Alexey A. Kovalev Alexandra A. Savelyeva |
| author_facet | Victor V. Kotlyar Eugeny G. Abramochkin Alexey A. Kovalev Alexandra A. Savelyeva |
| author_sort | Victor V. Kotlyar |
| collection | DOAJ |
| description | We introduce and investigate a novel Laguerre-Gaussian (LG) beam, different from the conventional modal LG beams, which conserve the transverse intensity structure (up to scale) on propagation. The proposed beam does not conserve its structure on free space propagation but possesses some interesting properties. This beam is Fourier-invariant, and it has an increased dark area both in the initial (waist) plane and in the far field. Thus, without changing the topological charge of the beam, varying the radial (lower) index of the associated Laguerre polynomial allows increasing or decreasing the effective diameter of the central dark spot in the intensity pattern. In addition, the beam is autofocusing, i.e., the intensity distribution at the Rayleigh distance from the waist has a shape of the light ring (at any value of the radial index) with the minimal diameter and with the maximal on-ring intensity. Such a beam can be adopted for microparticle manipulation. Increasing the dark area in the focus of a high-aperture spherical lens allows the simultaneous trapping of several absorbing microparticles into this dark area. |
| first_indexed | 2024-03-09T19:33:57Z |
| format | Article |
| id | doaj.art-bbd2e5236d7e4511ae367db68b055f66 |
| institution | Directory Open Access Journal |
| issn | 2304-6732 |
| language | English |
| last_indexed | 2024-03-09T19:33:57Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Photonics |
| spelling | doaj.art-bbd2e5236d7e4511ae367db68b055f662023-11-24T02:01:18ZengMDPI AGPhotonics2304-67322022-09-0191070810.3390/photonics9100708Laguerre-Gaussian Beams with an Increased Dark Area and AutofocusingVictor V. Kotlyar0Eugeny G. Abramochkin1Alexey A. Kovalev2Alexandra A. Savelyeva3Image Processing Systems Institute of the RAS—Branch of FSRC “Crystallography & Photonics” of the RAS, 151 Molodogvardeyskaya St., 443001 Samara, RussiaLebedev Physical Institute, 221 Novo-Sadovaya St., 443011 Samara, RussiaImage Processing Systems Institute of the RAS—Branch of FSRC “Crystallography & Photonics” of the RAS, 151 Molodogvardeyskaya St., 443001 Samara, RussiaImage Processing Systems Institute of the RAS—Branch of FSRC “Crystallography & Photonics” of the RAS, 151 Molodogvardeyskaya St., 443001 Samara, RussiaWe introduce and investigate a novel Laguerre-Gaussian (LG) beam, different from the conventional modal LG beams, which conserve the transverse intensity structure (up to scale) on propagation. The proposed beam does not conserve its structure on free space propagation but possesses some interesting properties. This beam is Fourier-invariant, and it has an increased dark area both in the initial (waist) plane and in the far field. Thus, without changing the topological charge of the beam, varying the radial (lower) index of the associated Laguerre polynomial allows increasing or decreasing the effective diameter of the central dark spot in the intensity pattern. In addition, the beam is autofocusing, i.e., the intensity distribution at the Rayleigh distance from the waist has a shape of the light ring (at any value of the radial index) with the minimal diameter and with the maximal on-ring intensity. Such a beam can be adopted for microparticle manipulation. Increasing the dark area in the focus of a high-aperture spherical lens allows the simultaneous trapping of several absorbing microparticles into this dark area.https://www.mdpi.com/2304-6732/9/10/708optical vortexLaguerre-Gaussian beamtopological chargeFourier-invariant beamdark spot of an optical vortexautofocusing |
| spellingShingle | Victor V. Kotlyar Eugeny G. Abramochkin Alexey A. Kovalev Alexandra A. Savelyeva Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing Photonics optical vortex Laguerre-Gaussian beam topological charge Fourier-invariant beam dark spot of an optical vortex autofocusing |
| title | Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing |
| title_full | Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing |
| title_fullStr | Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing |
| title_full_unstemmed | Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing |
| title_short | Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing |
| title_sort | laguerre gaussian beams with an increased dark area and autofocusing |
| topic | optical vortex Laguerre-Gaussian beam topological charge Fourier-invariant beam dark spot of an optical vortex autofocusing |
| url | https://www.mdpi.com/2304-6732/9/10/708 |
| work_keys_str_mv | AT victorvkotlyar laguerregaussianbeamswithanincreaseddarkareaandautofocusing AT eugenygabramochkin laguerregaussianbeamswithanincreaseddarkareaandautofocusing AT alexeyakovalev laguerregaussianbeamswithanincreaseddarkareaandautofocusing AT alexandraasavelyeva laguerregaussianbeamswithanincreaseddarkareaandautofocusing |