CN110109258B - Vortex light mode excitation method based on tapered micro-lens optical fiber - Google Patents
Vortex light mode excitation method based on tapered micro-lens optical fiber Download PDFInfo
- Publication number
- CN110109258B CN110109258B CN201910336871.3A CN201910336871A CN110109258B CN 110109258 B CN110109258 B CN 110109258B CN 201910336871 A CN201910336871 A CN 201910336871A CN 110109258 B CN110109258 B CN 110109258B
- Authority
- CN
- China
- Prior art keywords
- mode
- optical fiber
- vortex
- optical
- fiber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/09—Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for
- G02B27/0938—Using specific optical elements
- G02B27/095—Refractive optical elements
- G02B27/0955—Lenses
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/09—Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for
- G02B27/0938—Using specific optical elements
- G02B27/0994—Fibers, light pipes
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/32—Optical coupling means having lens focusing means positioned between opposed fibre ends
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Couplings Of Light Guides (AREA)
Abstract
The invention relates to a vortex light mode excitation method based on a tapered micro-lens optical fiber. According to the method, the conical micro-lens optical fiber replaces a common single-mode optical fiber and a ring-core optical fiber for dislocation, and the efficiency of dislocation excitation of vortex light beams is effectively improved due to the fact that the conical micro-lens optical fiber has a focusing characteristic. When the inclination angle between the two staggered optical fibers is zero, a first-order vortex light mode can be excited; when a certain inclination angle exists between the two staggered optical fibers, the excitation of a high-order vortex optical mode can be realized. Because the conical end of the conical micro-lens optical fiber is of an arc-shaped structure, the horizontal distance between the two optical fibers can not be increased when the two optical fibers are relatively inclined, and the efficiency of exciting the high-order vortex light mode is further improved.
Description
Technical Field
The invention relates to a mode for exciting vortex light in an optical fiber, belonging to the field of optical fiber communication and technology. The vortex light mode excitation method based on the tapered micro-lens optical fiber is characterized in that a method for exciting a vortex light mode based on the dislocation of a common single-mode optical fiber is improved, the vortex light mode is excited by the dislocation of the tapered micro-lens optical fiber instead of the common single-mode optical fiber, so that the coupling efficiency is improved to a certain extent, and in addition, on the basis of the dislocation distance, the relative inclination angle variable between the two optical fibers is increased, so that the excitation of a high-order vortex light mode can be realized.
Background
The vortex optical mode has a special spiral phase wavefront structure, the number of the modes has infinity, orthogonality exists among the modes, the characteristics enable the vortex optical mode to become a new degree of freedom of a control optical field after the states of phase, amplitude, polarization and the like, different vortex optical modes correspond to different data information, the existing optical communication capacity can be greatly improved, and besides, the vortex optical mode carrying orbital angular momentum is widely researched and applied in the fields of micro particle capture, atomic manipulation, quantum communication and the like.
The excitation methods of the vortex optical mode can be divided into two types, one is a spatial excitation method, and the excitation of the vortex optical mode needs to be realized by using a bulk optical device, such as a spiral phase plate method, a spatial light modulator method, a cylindrical lens mode conversion method and the like, and the methods inevitably have the problems of coupling difficulty and efficiency when spatial light is coupled into an optical fiber; the other type is an all-fiber excitation method, which does not need additional bulk optical devices, and utilizes the theory of coupling modes in the fiber to directly generate vortex optical modes in the fiber, such as a fiber grating method, a fused biconical taper coupler method, a dislocation excitation method and the like, but the fiber grating method, the coupler method and the like are the excitation of vortex optical modes realized on the basis of destroying the vortex fiber, and the excitation is irreversible, and the dislocation excitation method can obtain the vortex optical modes which are wanted on the basis of not destroying the vortex fiber. At present, the research on the method for exciting the vortex light mode in a dislocation way is carried out by using common single-mode fibers and few-mode fibers in a dislocation way, and the excited vortex light beam is only limited to one order and has the problem of low excitation efficiency.
Disclosure of Invention
The invention aims to provide a vortex optical mode excitation method based on a tapered micro-lens optical fiber, aiming at the defects of the prior art, the method can not damage a special optical fiber with a ring core, can improve the efficiency of dislocation excitation of a vortex optical mode, and can realize effective excitation of a high-order vortex optical mode.
In order to achieve the purpose, the invention adopts the following technical scheme:
a vortex light mode excitation method based on a tapered micro-lens optical fiber can use two optical fibers, one is the tapered micro-lens optical fiber which replaces a common single-mode optical fiber and can effectively improve the efficiency of exciting a vortex mode in a dislocation mode, and the other optical fiber is a ring-core optical fiber with a doped high-refractive-index ring and can realize stable transmission of a vortex light mode. By controlling the dislocation distance and the inclination angle between the two optical fibers, the excitation of vortex light modes with different orders can be realized.
In the vortex light mode excitation method based on the tapered micro-lens optical fiber, when the inclination angle between the two optical fibers is zero, the effective excitation of the first-order vortex light mode can be realized by adjusting the dislocation distance between the two optical fibers to a certain proper value. Wherein, replace ordinary single mode fiber with toper microlens optic fibre, the reason is that ordinary single mode fiber's emergent light can disperse when propagating in free space because of diffraction effect, mode field diameter can increase, lead to having some light to leak out from the cladding at the in-process of dislocation, reduce coupling efficiency, and the top microlens of toper microlens optic fibre has the focusing characteristic, light can assemble after being exported by toper microlens optic fibre, and then reduce mode field diameter, make the light of coupling to in the ring core optic fibre increase to some extent, coupling efficiency when arousing vortex optical mode is improved.
In the vortex optical mode excitation method based on the tapered micro-lens optical fiber, according to the theory that the transmission angles of all orders of modes in ray optics in the optical fiber are different, on the basis of exciting the first-order vortex optical mode in a staggered manner, a certain inclination angle is formed between the two staggered optical fibers, and the high-order vortex optical mode can be effectively excited. When a high-order vortex optical mode is excited by dislocation of a common single-mode fiber and a ring-core fiber, because the end face of the single-mode fiber is of a planar structure and has a certain inclination angle with the ring-core fiber, the relative horizontal distance between the two fibers is inevitably increased, so that light coupled into a high-refractive-index ring of the ring-core fiber is reduced, and the coupling efficiency is further reduced. When the conical micro-lens optical fiber is used for replacing a common single-mode optical fiber to carry out dislocation excitation on a high-order vortex optical mode, due to the arc-shaped structure of the micro-lens at the top end of the conical micro-lens optical fiber, when a certain inclination angle exists between two optical fibers for dislocation, the relative horizontal distance between the two optical fibers cannot be increased, and the coupling efficiency is improved.
Compared with the prior art, the invention has the following obvious prominent substantive characteristics and obvious advantages:
(1) the tapered micro-lens fiber is obtained by carrying out corrosion and arc discharge treatment on a common single-mode fiber, has simple preparation process and low cost, and can be manufactured in batches. The focusing characteristic of the micro lens at the cone tip improves the efficiency of exciting the vortex light mode based on the dislocation of the conical micro lens optical fiber.
(2) The end face of the conical micro-lens optical fiber is of an arc-shaped structure, when a high-order vortex light mode is excited by dislocation, the relative inclination angle between the two optical fibers needs to be increased, and the conical micro-lens optical fiber is adopted for dislocation, so that the relative horizontal distance between the two optical fibers cannot be increased when a certain inclination angle exists between the two optical fibers for dislocation, and the coupling efficiency is improved.
(3) The method for exciting the vortex optical mode in the dislocation mode can excite the vortex optical mode which is wanted by people by changing the parameters and the dislocation conditions of the tapered micro-lens optical fiber on the basis of not damaging the structure of the ring core optical fiber.
Drawings
The invention is further described below with reference to the accompanying drawings and the detailed description.
FIG. 1 is a misaligned portion of an excited vortex optical mode.
Fig. 2 is a graph showing the experimental results of the dislocation-excited first-order vortex light mode.
Fig. 3 is a graph showing the experimental results of the second order vortex optical mode excited by dislocation.
Detailed Description
The preferred embodiments of the present invention are described below with reference to the accompanying drawings:
the first embodiment is as follows:
referring to fig. 1, the vortex light mode excitation method based on the tapered microlens fiber is characterized in that the tapered microlens fiber (1) and the ring core fiber (2) are staggered, and the vortex light modes of different orders are excited by controlling the staggered distance and the inclined angle between the two fibers.
Example two:
this embodiment is substantially the same as the first embodiment, and is characterized in that:
the tapered microlensed fiber (1) has focusing properties that increase the coupling efficiency of light coupled into the ring-core fiber (2). When the inclination angle between the two optical fibers is zero, the dislocation distance between the two optical fibers is adjusted to a certain proper value, and a first-order vortex light mode can be effectively excited. When the inclination angle between the two optical fibers is a non-zero value, the dislocation distance and the inclination angle between the two optical fibers are adjusted to be proper values, and a high-order vortex light mode can be effectively excited.
Example three:
the vortex optical mode excitation method based on the tapered micro-lens optical fiber is characterized in that for the excitation of a first-order vortex optical mode, the tapered micro-lens optical fiber and a ring-core optical fiber are placed on two six-dimensional adjusting frames to be used as dislocation parts, the dislocation is realized by mainly adjusting three adjusting rods of XYZ to ensure that the two optical fibers are spatially staggered to a certain extent, a tunable laser is used as an input light source of a system, the output light wavelength of the tunable laser is adjusted to a communication waveband, a 1:1 optical fiber coupler is used for dividing the light into two paths, one path of light is input to the dislocation part, the dislocation part can refer to figure 1, but the inclination angle at the moment is zero, after the dislocation distance is adjusted to a certain proper value, the purity of a first-order mode excited in the ring-core optical fiber is maximum, pressure is applied to the ring-core optical fiber to obtain the first-order vortex optical mode, and the optical coupling, the output light of the coupler is input into the single-mode fiber, interference is carried out on the vortex light mode excited by the other path by means of the Mach-Zehnder interference system, generation of the vortex light mode is observed through interference fringes, and finally detection of the vortex light mode is achieved. The experimental result diagram of the dislocation excitation first-order vortex light mode is shown in fig. 2, and the first-order scalar mode excited by dislocation, the first-order vortex light mode generated after applying pressure and the interference fringes after interfering with gaussian light are sequentially arranged from left to right, wherein the counterclockwise direction and the clockwise direction of the fringes in the interference diagram respectively represent the positive order and the negative order of the vortex mode.
Example four:
the vortex light mode excitation method based on the tapered micro-lens optical fiber is different from the excitation of a first-order vortex light mode in that a certain inclination angle is added on the basis of dislocation to realize the excitation of a high-order vortex light mode, namely, an angle adjustment is required besides the adjustment of an XYZ adjusting rod, and the dislocation part of the vortex light mode is shown in figure 1. The dislocation distance and the inclination angle are adjusted to enable the dislocation distance and the inclination angle to reach appropriate values, the purity of the second order mode is the maximum, pressure is applied to the ring core optical fiber at the moment, a second order vortex optical mode can be obtained, an experimental result diagram is shown in fig. 3, the second order scalar mode excited by dislocation is sequentially arranged from left to right, the second order vortex optical mode generated after the pressure is applied, and interference fringes after the interference with Gaussian light are generated, wherein the anticlockwise and clockwise of the fringes in the interference diagram respectively represent the positive second order and the negative second order of the vortex optical mode.
Claims (3)
1. A vortex light mode excitation method based on a tapered micro-lens optical fiber is characterized in that the tapered micro-lens optical fiber (1) and a ring core optical fiber (2) are staggered, and the excitation of vortex light modes of different orders is realized by controlling the staggered distance and the inclined angle between the two optical fibers; when the inclination angle between the two optical fibers is a non-zero value, the dislocation distance and the inclination angle between the two optical fibers are adjusted to be proper values, and a high-order vortex light mode can be effectively excited.
2. The method of claim 1, wherein the vortex optical mode excitation method based on the tapered microlens fiber comprises: the tapered microlensed fiber (1) has focusing properties that increase the coupling efficiency of light coupled into the ring-core fiber (2).
3. The method of claim 1, wherein the vortex optical mode excitation method based on the tapered microlens fiber comprises: when the inclination angle between the two optical fibers is zero, the dislocation distance between the two optical fibers is adjusted to a certain proper value, and a first-order vortex light mode can be effectively excited.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910336871.3A CN110109258B (en) | 2019-04-25 | 2019-04-25 | Vortex light mode excitation method based on tapered micro-lens optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910336871.3A CN110109258B (en) | 2019-04-25 | 2019-04-25 | Vortex light mode excitation method based on tapered micro-lens optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110109258A CN110109258A (en) | 2019-08-09 |
| CN110109258B true CN110109258B (en) | 2020-11-24 |
Family
ID=67486601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910336871.3A Active CN110109258B (en) | 2019-04-25 | 2019-04-25 | Vortex light mode excitation method based on tapered micro-lens optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110109258B (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7590317B2 (en) * | 2005-03-31 | 2009-09-15 | John Crownover | High energy fiber optics laser delivery system with improved scrambling capabilities |
| CN103440895A (en) * | 2013-09-18 | 2013-12-11 | 哈尔滨理工大学 | Device and method for generating stable vortex beams by utilizing liquid-core optical fibers |
| CN108089267B (en) * | 2017-12-01 | 2019-08-30 | 华中科技大学 | A kind of optical-fiber type broadband light vortex converter |
-
2019
- 2019-04-25 CN CN201910336871.3A patent/CN110109258B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110109258A (en) | 2019-08-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Wang et al. | Generation and detection of structured light: a review | |
| Mao et al. | Generation of polarization and phase singular beams in fibers and fiber lasers | |
| CN110959232B (en) | Optical modulator based on optical fiber | |
| CN108089267B (en) | A kind of optical-fiber type broadband light vortex converter | |
| CN100371745C (en) | Method of generating hollow hight beam and tuning by utilizing optical fiber intermodal interference | |
| CN103149640B (en) | Device and method for generating axisymmetric polarized light | |
| Wang et al. | Orbital angular momentum in fibers | |
| CN113281845A (en) | OAM photon lantern based on spiral tapered fiber bundle and manufacturing and application thereof | |
| CN104698541A (en) | Generating device for radial polarized light | |
| CN105467610B (en) | For the fine laser dot-matrix generation device of the microscopical full polarization of stimulated emission depletion | |
| CN103944048A (en) | Femtosecond laser device based on single cladding neodymium optical fibers and ring cavity and manufacturing method | |
| CN111443496B (en) | Coupling device and method for realizing double-beam coaxial output | |
| CN212462334U (en) | Laser for generating column vector beam | |
| Zou et al. | Visible-wavelength all-fiber vortex laser | |
| CN110109258B (en) | Vortex light mode excitation method based on tapered micro-lens optical fiber | |
| CN103440895A (en) | Device and method for generating stable vortex beams by utilizing liquid-core optical fibers | |
| Vaity et al. | Exciting OAM modes in annular-core fibers via perfect OAM beams | |
| Kumar et al. | Generation and detection of optical vortices using all fiber-optic system | |
| Swartzlander, Jr | The optical vortex lens | |
| Ji et al. | Controlled generation of picosecond-pulsed higher-order Poincaré sphere beams from an ytterbium-doped multicore fiber amplifier | |
| CN103368069A (en) | A laser device structure for reducing high-order mode | |
| Yang et al. | Integrated all-fiber structures for generating doughnut beam arrays and hollow Bessel-like beams | |
| CN209981720U (en) | Double-arm structure annular light spot output continuous optical fiber laser | |
| CN104795720A (en) | Beam conversion device based on optical micro-cavity regulation | |
| CN220934587U (en) | Cylindrical vector light field generating device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |