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Jia A, Hong Y, Liu Q, Sun Y, Gao S, Sheng Y, Wang Y, Ding W. Selectively gas-filled anti-resonant hollow-core fibers for broadband high-purity LP 11 mode guidance. OPTICS LETTERS 2023; 48:1622-1625. [PMID: 37221725 DOI: 10.1364/ol.484663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 02/14/2023] [Indexed: 05/25/2023]
Abstract
An anti-resonant hollow-core fiber capable of propagating the LP11 mode with high purity and over a wide wavelength range is proposed and demonstrated. The suppression of the fundamental mode relies on the resonant coupling with specific gas selectively filled into the cladding tubes. After a length of 2.7 m, the fabricated fiber shows a mode extinction ratio of over 40 dB at 1550 nm and above 30 dB in a wavelength range of 150 nm. The loss of the LP11 mode is measured to be 2.46 dB/m at 1550 nm. We discuss the potential application of such fibers in high-fidelity high-dimensional quantum state transmission.
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2
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Joshi S, Khan SN, Kanseri B, Senthilkumaran P. Investigation of partially coherent vector vortex beams with non-isotropic states of spatial correlation. OPTICS EXPRESS 2022; 30:32230-32243. [PMID: 36242289 DOI: 10.1364/oe.463210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 06/26/2022] [Indexed: 06/16/2023]
Abstract
In this work, the far-field properties of non-isotropic partially coherent vector vortex beams (PCVVBs) are investigated both theoretically and experimentally. The term non-isotropic signifies that the spatial correlations between the parallel and orthogonal electric field components are distinguishable. It is found that self-orientation and shaping of intensity profile, correlation-induced polarization and depolarization are highly dependent on both the non-isotropic correlation parameters and Poincaré-Hopf index (PHI) of the beam. The simultaneous depolarization and polarization effects are due to the difference in the input correlation parameters that alter the state of polarization (SOP) and degree of polarization (DOP) distributions. The experimental results are in good agreement with the theoretical predictions. The distinguishability of correlation parameters at the source plane leads to significant changes on its intensity profile, DOP, and SOP distributions on far-field propagation, which may found potential applications in beam shaping, detecting and imaging atmospheric lidar, optical imaging and directional transportation where the self-rotation characteristic of beam plays an important role.
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3
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Wu G, Wu X, Gao S, Tu J, Zhou J, Sui Q, Liu W, Li Z. Multi-channel higher-order OAM generation and switching based on a mode selective interferometer. OPTICS EXPRESS 2022; 30:25093-25102. [PMID: 36237047 DOI: 10.1364/oe.463398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 06/07/2022] [Indexed: 06/16/2023]
Abstract
A multi-channel orbital angular momentum (OAM) mode generation and switching scheme is proposed and demonstrated based on an in-fiber mode selective interferometer (MSI), which is formed in a four-mode fiber. The MSI consists of two strong modulated long-period fiber gratings (LPFGs), which realizes the mode selected coupling between a target mode pair. With the optimized structural parameters, the MSI can couple a launched LP01 (or OAM0) into a desired higher-order azimuthal mode (HAM, LPl1 or OAM±l, l≥1) at multiple wavelength channels and generate the HAM with high-purity. To verify this concept, we fabricate two LPFGs in a four-mode fiber with designed distance and hence realize a MSI which can generate the second-order HAM (OAM2 or LP21) at 17 wavelength channels. The mode conversion efficiency is more than 90% at 17 wavelengths and the corresponding mode purity is no less than 97%, respectively. In addition, we also demonstrate that the selected mode pair (OAM0 and OAM2) can be switched at multiple channels by changing the state of the MSI. This MSI can also be used as a wavelength band-rejection filter on different spatial modes and find potential applications in optical communications and sensing.
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Wang T, Lu J, Yao H, Shi F, Meng L, Cheng P, Zeng X. Recent progress in all-fiber ultrafast high-order mode lasers. JPHYS PHOTONICS 2021. [DOI: 10.1088/2515-7647/abc898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract
Ultrafast high-order mode (HOM) lasers are a relatively new class of ultrafast optics. They play a significant role in the fieldsof scientific research and industrial applications due to the high peak power and unique properties of spatial intensity and polarization distribution. Generation of ultrafast HOM beams in all-fiber systems has become an important research direction. In this paper, all-fiber mode conversion techniques, pulsed HOM laser strategies, and few-mode/multi-mode fiber (FMF/MMF) lasers are reviewed. The main motivation of this review is to highlight recent advances in the field of all-fiber ultrafast HOM lasers, for example, generating different HOM pulses based on fiber mode converters and mode-locking in the FMF/MMF lasers. These results suggest that mode selective coupler can be used as a broad bandwidth mode converter with fast response and HOM can be directly oscillated in the FMF/MMF laser cavity with high stability. In addition, spatiotemporal mode-locking in the FMF/MMF is also involved. It is believed that the development of all-fiber ultrafast HOM lasers will continue to deepen, thus laying a good foundation for future applications.
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Schlangen S, Bremer K, Böhm S, Wellmann F, Steinke M, Neumann J, Roth B, Overmeyer L. Grating assisted glass fiber coupler for mode selective co-directional coupling. OPTICS LETTERS 2019; 44:2342-2345. [PMID: 31042218 DOI: 10.1364/ol.44.002342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
To keep pace with the increasing demand of transmission capacity, space division multiplexing technologies are currently intensively investigated. In this context, mode selective glass fiber couplers are of great interest due to their compatibility with existing glass fiber networks. In this work, we present a novel type of mode selective glass fiber coupler for co-directional coupling based on fiber gratings and fused asymmetric fibers. The achieved mode selective coupling efficiency agrees well with numerical simulations performed for comparison. The benefits of the grating approach are a lower mode crosstalk and a simple adaption of the propagation constants through changing of the grating-period.
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Carbon Nanotube Mode-Locked Fiber Laser Generating Cylindrical Vector Beams with a Two-Mode Fiber Bragg Grating. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8040643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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7
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Jiang Y, Ren G, Shen Y, Xu Y, Jin W, Wu Y, Jian W, Jian S. Two-dimensional tunable orbital angular momentum generation using a vortex fiber. OPTICS LETTERS 2017; 42:5014-5017. [PMID: 29216168 DOI: 10.1364/ol.42.005014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
We demonstrate the two-dimensional tunable orbital angular momentum (OAM) generation in a ring-core (vortex) fiber. The LP11 mode generated by an all fiber fused coupler is coupled into a vortex fiber. Because the vector modes of the LP11 mode group in the vortex fiber are no longer degenerate, the mode status will change between linearly polarized modes (LPMs) and complex OAM modes periodically during propagation. The generated OAM can be tuned smoothly by filtering the mixed mode with different polarization directions or changing the wavelength at a certain polarization directions. The two-dimensional tuning of OAM from l=-1 to l=+1 is experimentally demonstrated in an all fiber OAM generator.
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8
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Wang W, Wu J, Chen K, Jin W, Chiang KS. Ultra-broadband mode converters based on length-apodized long-period waveguide gratings. OPTICS EXPRESS 2017; 25:14341-14350. [PMID: 28789020 DOI: 10.1364/oe.25.014341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/12/2017] [Indexed: 06/07/2023]
Abstract
We propose an ultra-broadband mode converter based on the structure of a length-apodized long-period grating, where π-phase shifts are introduced at strategic locations of the grating profile. Using a 3-section length-apodized grating structure, we design and fabricate an LP01-LP11a and an LP01-LP11b mode converter with a sidewall grating and a surface grating formed along a polymer channel waveguide, respectively. The fabricated LP01-LP11a and LP01-LP11b mode converters provide a conversion efficiency higher than 99% over a bandwidth of ~120 nm and ~150 nm, respectively, or a conversion efficiency higher than 90% over a bandwidth of ~180 nm and ~300 nm, respectively. The transmission characteristics of these devices are weakly sensitive to polarization and temperature variations. These mode converters can find applications in ultra-broadband mode-division-multiplexing transmission systems based on few-mode fibers and the design principle can be applied to general grating-based mode-coupling devices for a wide range of applications.
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9
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Chen MY, Cao GD, Tong YQ, Wang L. High-order mode conversion based on adiabatical mode evolution for mode division multiplexing applications. APPLIED OPTICS 2017; 56:5125-5130. [PMID: 29047562 DOI: 10.1364/ao.56.005125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
Mode conversion based on adiabatical mode evolution in a two-core configuration is investigated. The configuration can convert all the launching modes to higher-order modes from one port and convert all the launching modes to lower-order modes from another port. Mode conversion between the two degenerated high-order modes is also demonstrated numerically. The mode conversion feature is only dependent on the relationship between the effective mode indices of the two cores in the configuration, which shows the characteristics of high flexibility and large fabrication tolerance.
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10
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Liu T, Chen S, Qi X, Hou J. High-power transverse-mode-switchable all-fiber picosecond MOPA. OPTICS EXPRESS 2016; 24:27821-27827. [PMID: 27906350 DOI: 10.1364/oe.24.027821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A high-power transverse-mode-switchable all-fiber picosecond laser in a master-oscillator power-amplifier (MOPA) configuration is demonstrated. The master oscillator is a gain-switched laser diode delivering picosecond pulses with 25 MHz repetition rate at the wavelength of 1.06 μm. After multi-stage amplification in ytterbium-doped fibers, the average output power is scaled to 117 W. A mechanical long-period grating is employed as a fiber mode convertor to achieve controllable conversion from the fundamental (LP01) to the second-order (LP11) mode. Efficient mode conversion is demonstrated and the output characteristics for both modes are investigated. It is shown that LP01 and LP11 modes have nearly identical optical-to-optical conversion efficiency during amplification, but the nonlinear spectral degradation is significantly alleviated for LP11 mode operation. Owing to the compact all-fiber architecture, this high-power transverse-mode-switchable fiber laser is reliable during long-term operation and thus promising for many practical applications, e.g. high-resolution laser micro-processing.
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11
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Zhang M, Chen K, Jin W, Chiang KS. Electro-optic mode switch based on lithium-niobate Mach-Zehnder interferometer. APPLIED OPTICS 2016; 55:4418-4422. [PMID: 27411197 DOI: 10.1364/ao.55.004418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We propose an electro-optic mode switch based on an optical waveguide Mach-Zehnder interferometer fabricated with x-cut lithium niobate by the annealed proton exchange process. The device can switch between the fundamental mode and the higher-order mode with a low driving voltage. Our typical fabricated device, which has a total length of ∼24 mm, shows a mode extinction ratio of ∼35 dB and a 20-dB bandwidth of ∼12 nm at the wavelength 1552 nm, when driven at a voltage of 1.7 V at 26°C. High performance can be obtained at any wavelength in the C+L band with a driving voltage varying by no more than 3 V. The proposed mode switch is easy to fabricate and could find applications in reconfigurable mode-division-multiplexing systems.
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Pelegrina-Bonilla G, Hausmann K, Sayinc H, Morgner U, Neumann J, Kracht D. Analysis of the modal evolution in fused-type mode-selective fiber couplers. OPTICS EXPRESS 2015; 23:22977-22990. [PMID: 26368403 DOI: 10.1364/oe.23.022977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Fused-type mode-selective fiber couplers exciting the LP(11) mode are fabricated by well-defined fiber cladding reduction, pretapering and fusion. At a wavelength of 905 nm 80 % of the injected power in the single-mode fiber was transmitted in the few-mode fiber selectively exciting the LP(11) mode. The coupling behavior was experimentally investigated for the case of strong as well as weak fusion. Numerical simulations based on the super-mode coupling approach were used to estimate fabrication parameters and to discuss the modal evolution in arbitrarily fused couplers. The influence of changes in the coupler geometry on the super-modes and their modal weighting are analyzed by calculations of the effective refractive index and by modal decomposition.
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13
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Mellah H, Zhang X, Shen D. Analysis of optical fiber-based LP(01) ↔ LP(02) mode converters for the O-, S-, and C-Band. APPLIED OPTICS 2015; 54:5568-5575. [PMID: 26192862 DOI: 10.1364/ao.54.005568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This paper proposes a double fiber taper-based mode converter that converts LP(01) to LP(02) and vice versa. The first taper is used to convert LP(01) to some higher order LP(0m) (m>1) modes while the second taper suppresses the undesired higher order modes (m>2) and results in LP(02) overwhelmingly dominated. A simulation shows that conversion efficiency of almost 100% at the central wavelength of O-, S-, and C-Band, and above 98% over the S- and C-Band was achieved. Moreover, suppression of undesired higher order modes is more than 10 dB over the whole O-, S-, and C-Band. In particular, the suppression is more than 19 dB for the whole C-Band. The analysis also shows that the performance of the mode converter is not sensitive to slight variations of the converter's parameters. The same converter also can be used to convert LP(02) back to LP(01). It is shown that conversion efficiency higher than 99% and suppression of undesired higher order modes higher than 30 dB can be obtained. Further, a (de)multiplexer for an LP(02) and an LP(01) mode was designed using the mode converter combined with a symmetric directional coupler. The multiplexer is broadband and has an insertion loss less than 0.5 dB in the C-Band.
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14
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Ramachandran S, Gregg P, Kristensen P, Golowich SE. On the scalability of ring fiber designs for OAM multiplexing. OPTICS EXPRESS 2015; 23:3721-3730. [PMID: 25836225 DOI: 10.1364/oe.23.003721] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The promise of the infinite-dimensionality of orbital angular momentum (OAM) and its application to free-space and fiber communications has attracted immense attention in recent years. In order to facilitate OAM-guidance, novel fibers have been proposed and developed, including a class of so-called ring-fibers. In these fibers, the wave-guiding region is a high-index annulus instead of a conventional circular core, which for reasons related to polarization-dependent differential phase shifts for light at waveguide boundaries, leads to enhanced stability for OAM modes. We review the theory and implementation of this nascent class of waveguides, and discuss the opportunities and limitations they present for OAM scalability.
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15
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Ploss D, Kriesch A, Pfeifer H, Banzer P, Peschel U. Generation and subwavelength focusing of longitudinal magnetic fields in a metallized fiber tip. OPTICS EXPRESS 2014; 22:13744-13754. [PMID: 24921567 DOI: 10.1364/oe.22.013744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We demonstrate experimentally and numerically that in fiber tips as they are used in NSOMs azimuthally polarized electrical fields (|E(azi)|2 / |E(tot)|2 ≈55% ± 5% for λ0 = 1550 nm), respectively subwavelength confined (FWHM ≈450 nm ≈λ0/3.5) magnetic fields, are generated for a certain tip aperture diameter (d = 1.4 μm). We attribute the generation of this field distribution in metal-coated fiber tips to symmetry breaking in the bend and subsequent plasmonic mode filtering in the truncated conical taper.
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16
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Chen MY, Zhou J. Design of add-drop multiplexer based on multi-core optical fibers for mode-division multiplexing. OPTICS EXPRESS 2014; 22:1440-1451. [PMID: 24515151 DOI: 10.1364/oe.22.001440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A multi-core fiber coupler is proposed to extract one of the modes in a few-mode optical fiber from a light beam, leaving the other modes undisturbed, and allowing a new signal to be retransmitted on that mode. Selective coupling of higher-order modes from a few-mode optical fiber can be realized by increasing the coupling length difference of the modes in the fiber using the multi-core configuration. Low cross-talk and wide bandwidth operation are realized owing to the fact that only one mode can be effectively coupled.
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17
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Yerolatsitis S, Gris-Sánchez I, Birks TA. Adiabatically-tapered fiber mode multiplexers. OPTICS EXPRESS 2014; 22:608-617. [PMID: 24515021 DOI: 10.1364/oe.22.000608] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Simple all-fiber three-mode multiplexers were made by adiabatically merging three dissimilar single-mode cores into one multimode core. This was achieved by collapsing air holes in a photonic crystal fiber and (in a separate device) by fusing and tapering separate telecom fibers in a fluorine-doped silica capillary. In each case the LP01 mode and both LP11 modes were individually excited from three separate input cores, with losses below 0.3 and 0.7 dB respectively and mode purities exceeding 10 dB. Scaling to more modes is challenging, but would be assisted by using single-mode fibers with a smaller ratio of cladding to core diameter.
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18
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Leon-Saval SG, Fontaine NK, Salazar-Gil JR, Ercan B, Ryf R, Bland-Hawthorn J. Mode-selective photonic lanterns for space-division multiplexing. OPTICS EXPRESS 2014; 22:1036-44. [PMID: 24515063 DOI: 10.1364/oe.22.001036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We demonstrate a 3x1 fiber-based photonic lantern spatial-multiplexer with mode-selectivity greater than 6 dB and transmission loss of less than 0.3 dB. The total insertion loss of the mode-selective multiplexers when coupled to a graded-index few-mode fiber was < 2 dB. These mode multiplexers showed mode-dependent loss below 0.5 dB. To our knowledge these are the lowest insertion and mode-dependent loss devices, which are also fully compatible with conventional few-mode fiber technology and broadband operation.
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19
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Zhang XB, Zhu X, Chen X, Li HQ, Peng JG, Dai NL, Li JY. A hollow beam supercontinuum generation by the supermode superposition in a GeO2 doped triangular-core photonic crystal fiber. OPTICS EXPRESS 2012; 20:19799-19805. [PMID: 23037032 DOI: 10.1364/oe.20.019799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A GeO2 doped triangular-core photonic-crystal fiber (PCF) is designed and fabricated to allow the generation of a hollow beam through a nonlinear-optical transformation by femtosecond pulses at 1040 nm from a high power Yb-doped PCF laser oscillator. The hollow beam supercontinuum is obtained at far field by adjusting incident light polarization to excite the high order supermode, behaving as a mode convertor. The supercontinuum ranging from 540 to 1540 nm is achieved with an average power of 1.04 W.
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Affiliation(s)
- Xin-ben Zhang
- Wuhan National Laboratory of Optoelectronic, Huazhong University of Science and Technology, 430074 Wuhan, China
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20
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Chen Y, Yan L, Rishøj L, Steinvurzel P, Ramachandran S. Dynamically tunable optical bottles from an optical fiber. OPTICS LETTERS 2012; 37:3327-3329. [PMID: 23381246 DOI: 10.1364/ol.37.003327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Optical fibers have long been used to impose spatial coherence to shape free-space optical beams. Recent work has shown that one can use higher order fiber modes to create more exotic beam profiles. We experimentally generate optical bottles from Talbot imaging in the coherent superposition of two fiber modes excited with long period gratings, and obtain a 28 μm × 6 μm bottle with controlled contrast up to 10.13 dB. Our geometry allows for phase tuning of one mode with respect to the other, which enables us to dynamically move the bottle in free space.
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Affiliation(s)
- Yuhao Chen
- Boston University, Department of Electrical and Computer Engineering, Boston, Massachusetts 02118, USA
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21
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Ju J, Xuan HF, Jin W, Liu S, Ho HL. Selective opening of airholes in photonic crystal fiber. OPTICS LETTERS 2010; 35:3886-3888. [PMID: 21124554 DOI: 10.1364/ol.35.003886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We introduce a femtosecond-laser-based technique for selective opening of airholes in photonic crystal fibers (PCFs). With this technique, selective filling and inflation of the airholes in the PCF cladding are demonstrated. The technique may find important applications in tailoring or altering PCF characteristics and make it possible to seamlessly integrate various components/functions into PCFs.
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Affiliation(s)
- Jian Ju
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
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22
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Ramachandran S, Kristensen P, Yan MF. Generation and propagation of radially polarized beams in optical fibers. OPTICS LETTERS 2009; 34:2525-2527. [PMID: 19684837 DOI: 10.1364/ol.34.002525] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Beams with polarization singularities have attracted immense recent attention in a wide array of scientific and technological disciplines. We demonstrate a class of optical fibers in which these beams can be generated and propagated over long lengths with unprecedented stability, even in the presence of strong bend perturbations. This opens the door to exploiting nonlinear fiber optics to manipulate such beams. This fiber also possesses the intriguingly counterintuitive property of being polarization maintaining despite being strictly cylindrically symmetric, a prospect hitherto considered infeasible with optical fibers.
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Nandi P, Chen Z, Witkowska A, Wadsworth WJ, Birks TA, Knight JC. Characterization of a photonic crystal fiber mode converter using low coherence interferometry. OPTICS LETTERS 2009; 34:1123-1125. [PMID: 19340240 DOI: 10.1364/ol.34.001123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The relative group delay of the different modes present in an all-fiber LP11 mode converter at a central wavelength of 750 nm is observed using low coherence interferometric imaging. We have simultaneously measured the relative group delay and computed the intensity and the phase distribution of the modes emitted from the mode converter end face using a Fourier technique, providing unequivocal identification of the modes involved.
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Affiliation(s)
- Purnananda Nandi
- Centre for Photonics and Photonic Materials, Department of Physics, University of Bath, Bath, UK.
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