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11 pages, 6537 KiB

Open AccessArticle

Cavity Wavelength on Erbium-Doped Fiber Ring Laser Depending on Fabry–Pérot Etalon Steering Angle

by Cheng-Kai Yao, Ting-Po Fan, Ming-Che Chan and Peng-Chun Peng

Appl. Sci. 2025, 15(2), 822; https://doi.org/10.3390/app15020822 - 15 Jan 2025

Viewed by 1010

This study presents the liquid crystal Fabry–Pérot etalon (LC-FP) as the preferred laser wavelength tuning solution within a erbium-doped fiber ring laser architecture. The laser cavity wavelength can be adjusted by applying varying voltages to the LC-FP. Furthermore, tuning the laser wavelength can [...] Read more.

This study presents the liquid crystal Fabry–Pérot etalon (LC-FP) as the preferred laser wavelength tuning solution within a erbium-doped fiber ring laser architecture. The laser cavity wavelength can be adjusted by applying varying voltages to the LC-FP. Furthermore, tuning the laser wavelength can be facilitated by modifying the incident light through changes in the steering angle of the LC-FP, which is attributed to the angular dispersion characteristics of the device. The operational range for the steering angle of the LC-FP is ± 4 to 18 degrees. This architectural framework is adept at facilitating the generation of single-wavelength and dual-wavelength lasers within the C band. The tunable range for a single wavelength is approximately 13 nm, while the tunable range for dual wavelengths is around 14 nm, with a wavelength spacing of approximately 17.5 nm. These capabilities are primarily influenced by the operational wavelength of the erbium-doped fiber amplifier (EDFA), the operating wavelength of the collimator that directs the fiber optic beam into the LC-FP, and the fixed thickness of the LC-FP. Full article

(This article belongs to the Section Optics and Lasers)

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12 pages, 9124 KiB

Open AccessArticle

Vibration-Induced Sweeping Operation in Fiber Lasers

by Ekaterina K. Kashirina, Ivan A. Lobach and Sergey I. Kablukov

Photonics 2024, 11(8), 731; https://doi.org/10.3390/photonics11080731 - 5 Aug 2024

Cited by 1 | Viewed by 1128

Abstract

A new vibration-based mechanism of optical frequency/wavelength sweeping in fiber lasers induced by optical path length modulation of a laser cavity section is proposed. The mechanism is implemented for an erbium-doped fiber ring laser with a saturable absorber. Without the vibrations, the laser [...] Read more.

A new vibration-based mechanism of optical frequency/wavelength sweeping in fiber lasers induced by optical path length modulation of a laser cavity section is proposed. The mechanism is implemented for an erbium-doped fiber ring laser with a saturable absorber. Without the vibrations, the laser generates a single longitudinal mode (SLM) radiation. We show experimentally for the first time that mechanical vibrations of the laser cavity section can lead to mode dynamics in both frequency and time domains. The possibility of obtaining various mode dynamics, such as vibration-induced sweeping in a wavelength range of up to 2.2 nm or SLM generation with periodic mode hopping between two fixed longitudinal modes depending on the pump wavelength, is experimentally shown. In this vibration-based approach, the interval between changes in the laser cavity modes has good stability, because it directly relates to the vibration period. Full article

(This article belongs to the Special Issue A Recent Progress in Single Frequency Lasers: Development and Applications)

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13 pages, 3540 KiB

Open AccessArticle

Broad, Tunable and Stable Single-Frequency Erbium Fiber Compound-Ring Lasers Based on Parallel and Series Structures in L-Band Operation

by Yu-Ting Lai, Lan-Yin Chen, Teng-Yao Yang, Tsu-Hsin Wu, Chien-Hung Yeh, Kuan-Ming Cheng, Chun-Yen Lin, Chi-Wai Chow and Shien-Kuei Liaw

Photonics 2024, 11(7), 628; https://doi.org/10.3390/photonics11070628 - 1 Jul 2024

Cited by 2 | Viewed by 1173

Abstract

In this demonstration, we present two erbium-doped fiber (EDF) lasers, with series and parallel three sub-ring configurations, respectively, to achieve tunable channel output and stable single longitudinal mode (SLM) operation in the L-band range. Here, the fiber ring cavity contains the L-band EDF [...] Read more.

In this demonstration, we present two erbium-doped fiber (EDF) lasers, with series and parallel three sub-ring configurations, respectively, to achieve tunable channel output and stable single longitudinal mode (SLM) operation in the L-band range. Here, the fiber ring cavity contains the L-band EDF as a gain medium. Based on the measured results of the two quad-ring structures of the EDF lasers, tunable output bandwidth for the two lasers can be obtained from 1558.0 to 1618.0 nm simultaneously. All the 3 dB linewidths measured for both fiber lasers are 312.5 Hz over the effective wavelength output range. Furthermore, the related optical signal-to-noise ratio (OSNR), output power, output stabilities of the central wavelength and power, and equal output power range of the two proposed EDF lasers are also examined and discussed. Full article

(This article belongs to the Special Issue Recent Advancements in Tunable Laser Technology)

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14 pages, 3394 KiB

Open AccessArticle

High-Performance Fiber Ring Laser Based on Polarization Space Parity-Time Symmetry Breaking

by Fengling Zhang, Zhengmao Wu, Xin Tong and Guangqiong Xia

Photonics 2024, 11(6), 501; https://doi.org/10.3390/photonics11060501 - 25 May 2024

Cited by 1 | Viewed by 1880

Abstract

This work proposes and experimentally demonstrates a high-performance polarization space parity-time (PT) symmetric fiber ring laser to achieve a low-noise, narrow-linewidth, and highly stable single-longitudinal-mode output. The gain/loss and coupling coefficients are regulated by adjusting a polarization controller (PC) and the pumping current [...] Read more.

This work proposes and experimentally demonstrates a high-performance polarization space parity-time (PT) symmetric fiber ring laser to achieve a low-noise, narrow-linewidth, and highly stable single-longitudinal-mode output. The gain/loss and coupling coefficients are regulated by adjusting a polarization controller (PC) and the pumping current of an erbium-doped fiber amplifier (EDFA) within the ring cavity. The results show that the single longitudinal mode oscillation of the laser can be implemented by PT symmetry breaking. The frequency noise spectral density and the linewidth characteristics of the laser are evaluated by the short-delay self-heterodyne method. The results reveal that excellent low-frequency noise (181 Hz²/Hz at a 10 kHz offset frequency) and narrow fundamental linewidth (68 Hz) can be achieved. Additionally, the laser exhibits outstanding stability with only 0.64 pm wavelength drift over 30 min. By tuning an optical tunable filter (OTF), the wavelength tunable range of the laser can cover the entire C-band. Furthermore, the impacts of different fiber length on the frequency noise spectral density and the filter bandwidth on stability are analyzed, offering guidance for component selection in such laser systems. Full article

(This article belongs to the Special Issue Advanced Lasers and Their Applications, 2nd Edition )

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16 pages, 12591 KiB

Open AccessArticle

Evaluation of an Erbium-Doped Fiber Ring Laser as an Edge Filtering Device for Fiber Bragg Grating Sensor Interrogation

by Nikolaos A. Stathopoulos, Christos Lazakis, Iraklis Simos and Christos Simos

Photonics 2024, 11(5), 407; https://doi.org/10.3390/photonics11050407 - 27 Apr 2024

Cited by 1 | Viewed by 1798

Abstract

An easy-to-implement and cost-effective Fiber Bragg Grating (FBG) sensor interrogation technique based on a ring Erbium-Doped Fiber Laser (EDFL) topology is proposed and experimentally assessed. The FBG sensor is part of the EDFL cavity and must have a central wavelength located within the [...] Read more.

An easy-to-implement and cost-effective Fiber Bragg Grating (FBG) sensor interrogation technique based on a ring Erbium-Doped Fiber Laser (EDFL) topology is proposed and experimentally assessed. The FBG sensor is part of the EDFL cavity and must have a central wavelength located within the linear region of the EDF’s amplified spontaneous emission (ASE) spectrum, which occurs at between 1530 and 1540 nm. In this manner, the wavelength-encoded response of the FBG under strain is converted to a linear variation in the laser output power, removing the need for spectrum analysis as well as any limitations from the use of external edge-filtering components. In addition, the laser linewidth is significantly reduced with respect to the FBG bandwidth, thus improving the resolution of the system, whereas its sensitivity can be controlled through pumping power. The performance of the system has been characterized by modeling and experiments for EDFs with different lengths, doping concentrations, and pumping power levels. The influence of mode-hopping in the laser cavity on the resolution and accuracy of the system has also been investigated. Full article

(This article belongs to the Special Issue Fiber Optic Sensors: Science and Applications)

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12 pages, 2802 KiB

Open AccessArticle

L-Band Erbium Fiber Laser with Tunable and Narrow Sub-kHz Linewidth Output

by Lan-Yin Chen, Yu-Ting Lai, Chien-Hung Yeh, Chun-Yen Lin, Kuan-Ming Cheng, Jing-Heng Chen and Chi-Wai Chow

Appl. Sci. 2023, 13(21), 11770; https://doi.org/10.3390/app132111770 - 27 Oct 2023

Cited by 1 | Viewed by 1849

Abstract

In this paper, a wavelength-selectable erbium-doped fiber (EDF) laser in L-band bandwidth with a simple structure and low cost is described. To obtain stable single-longitudinal-mode (SLM) and narrow laser linewidth, the 2 m unpumped EDF-based saturable absorber (SA) and 100 m single-mode fiber [...] Read more.

In this paper, a wavelength-selectable erbium-doped fiber (EDF) laser in L-band bandwidth with a simple structure and low cost is described. To obtain stable single-longitudinal-mode (SLM) and narrow laser linewidth, the 2 m unpumped EDF-based saturable absorber (SA) and 100 m single-mode fiber (SMF)-induced Rayleigh backscattering (RB) injection effect are cascaded in the ring cavity of the fiber laser. The EDF SA and feedback RB injection can cause the auto-tracking ultra-narrow bandwidth filter effect to suppress the multiple longitudinal mode oscillations and narrow the laser linewidth. Thus, the tunable SLM wavelength output of the EDF laser with sub-kHz linewidth can be achieved. In the measurement, two EDF ring lasers can be executed when the placement of EDF-based SA and SMF-induced RB are switched to experiment with different output characteristics. The experimental results show that the wavelength bandwidths of the two lasers are between 1558.0 and 1618.0 nm. Additionally, the optimal optical signal-to-noise ratio (OSNR), wavelength linewidth, output power, and stability of the presented EDF laser configuration are also achieved and discussed. Full article

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17 pages, 8395 KiB

Open AccessArticle

Dual Regime Mode-Locked and Q-Switched Erbium-Doped Fiber Laser by Employing Graphene Filament–Chitin Film-Based Passive Saturable Absorber

by Siti Nur Fatin Zuikafly, Harith Ahmad, Mohd Faizal Ismail, Mohd Azizi Abdul Rahman, Wira Jazair Yahya, Nurulakmar Abu Husain, Khairil Anwar Abu Kassim, Hafizal Yahaya and Fauzan Ahmad

Micromachines 2023, 14(5), 1048; https://doi.org/10.3390/mi14051048 - 14 May 2023

Cited by 5 | Viewed by 2252

Abstract

We investigate the dynamics of high energy dual regime unidirectional Erbium-doped fiber laser in ring cavity, which is passively Q-switched and mode-locked through the use of an environmentally friendly graphene filament–chitin film-based saturable absorber. The graphene–chitin passive saturable absorber allows the option for [...] Read more.

We investigate the dynamics of high energy dual regime unidirectional Erbium-doped fiber laser in ring cavity, which is passively Q-switched and mode-locked through the use of an environmentally friendly graphene filament–chitin film-based saturable absorber. The graphene–chitin passive saturable absorber allows the option for different operating regimes of the laser by simple adjustment of the input pump power, yielding, simultaneously, highly stable and high energy Q-switched pulses at 82.08 nJ and 1.08 ps mode-locked pulses. The finding can have applications in a multitude of fields due to its versatility and the regime of operation that is on demand. Full article

(This article belongs to the Special Issue Semiconductors and Nanostructures for Electronics and Photonics)

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15 pages, 2529 KiB

Open AccessArticle

Linewidth Narrowing of a Dual Wavelength-Selectable, Ring Cavity Erbium-Doped Fiber Laser Using a Saturable Absorber

by Ebuka E. Okafor, Frank N. Igboamalu, Khmaies Ouahada and Habib Hamam

Photonics 2023, 10(5), 522; https://doi.org/10.3390/photonics10050522 - 2 May 2023

Cited by 2 | Viewed by 2366

Abstract

The narrow linewidth fiber laser is useful in applications such as fiber sensing, optical communications, and spectroscopy. This paper presents an investigation of the model and an experiment of a stable, wavelength-selective, narrow linewidth, ring cavity erbium-doped fiber laser incorporating two fiber Bragg [...] Read more.

The narrow linewidth fiber laser is useful in applications such as fiber sensing, optical communications, and spectroscopy. This paper presents an investigation of the model and an experiment of a stable, wavelength-selective, narrow linewidth, ring cavity erbium-doped fiber laser incorporating two fiber Bragg gratings (FBG) at 1530.18 nm and 1550.08 nm, respectively. An F-P tunable filter was used to select a specific wavelength after optimizing the spectral output from the two FBGs to measure their respective linewidths. The erbium-doped ring fiber laser was optimized by adjusting the optical cavity loss using a variable optical coupler at a coupling ratio of 95%. The variable coupler was set to an optimal coupling ratio of 95%, where the spectral output powers of 3.4 mW at 1530.18 nm and 3.1 mW at 1550.08 nm were achieved as the optimal fiber laser output powers. The balanced output power had an optical signal-to-noise ratio of (OSNR) of 61 dB for each wavelength. The linewidth was measured for both wavelengths without saturable absorbers, and 27.7 kHz and 28.3 kHz for 1530.18 nm and 1550.08 nm were obtained. Using the saturable absorber, the linewidths were narrowed to 25.3 KHz and 21.1 kHz for 1530.18 nm and 1550.08 nm, respectively. Full article

(This article belongs to the Topic Advance and Applications of Fiber Optic Measurement)

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9 pages, 2540 KiB

Open AccessArticle

Black Phosphorus Coated D-Shape Fiber as a Mode-Locker for Picosecond Soliton Pulse Generation

by Turki Ali Alghamdi, Somaya Adwan, Hamzah Arof and Sulaiman Wadi Harun

Crystals 2023, 13(5), 740; https://doi.org/10.3390/cryst13050740 - 27 Apr 2023

Cited by 13 | Viewed by 1592

Abstract

We demonstrate the production of a picosecond pulse from an Erbium laser cavity using black phosphorous (BP) on side-polished fiber saturable absorber (SA) as a mode-locker. The surface of the fiber was removed utilizing a polishing wheel, and then BP was mechanically deposited [...] Read more.

We demonstrate the production of a picosecond pulse from an Erbium laser cavity using black phosphorous (BP) on side-polished fiber saturable absorber (SA) as a mode-locker. The surface of the fiber was removed utilizing a polishing wheel, and then BP was mechanically deposited onto it to develop an excellent evanescent field on the polished surface area. The SA device was used in a 56 m long Erbium-doped fiber laser (EDFL) ring cavity to generate soliton mode-locked pulses with a center wavelength of 1556.2 nm and a 3 dB spectral bandwidth of 2.2 nm. Stable 3.48 MHz soliton pulses with pulse width as short as 1.17 ps were achievable by setting the pump power within 92 mW to 145 mW. The highest pulse energy and peak power obtainable were 5.4 nJ and 4.7 kW, respectively. The results show that BP deposited onto side-polished fiber can be used as an SA in an EDFL cavity. Its easy construction makes it suitable for producing a portable mode-locked laser source. Full article

(This article belongs to the Special Issue Advances in Optical Fibers, Devices and Applications)

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11 pages, 1987 KiB

Open AccessEditor’s ChoiceCommunication

All-Fiber Laser Feedback Interferometry for Sequential Sensing of In-Plane and Out-of-Plane Displacements

by Zhanwu Xie, Meng Zhang, Jie Li, Wei Xia and Dongmei Guo

Photonics 2023, 10(4), 480; https://doi.org/10.3390/photonics10040480 - 21 Apr 2023

Cited by 1 | Viewed by 1834

Abstract

In this paper, an all-fiber laser feedback interferometer (LFI) with a diffraction grating was developed for sequential measurement of in-plane and out-of-plane displacements without changing the optical arrangement. When the light emitted from an erbium-doped fiber ring laser is incident on a reflection [...] Read more.

In this paper, an all-fiber laser feedback interferometer (LFI) with a diffraction grating was developed for sequential measurement of in-plane and out-of-plane displacements without changing the optical arrangement. When the light emitted from an erbium-doped fiber ring laser is incident on a reflection grating at the Littrow angle, the diffracted light will return into the laser cavity along the original path, thus generating laser feedback interference. Experimental results reveal that the all-fiber system could achieve a precision of 40 nm in both in-plane and out-of-plane displacements sensing. Compared with the traditional all-fiber LFI, the proposed sensing system transfers the measuring scale from laser wavelength to grating period, and it has the advantages of good anti-interference performance and reliability. Full article

(This article belongs to the Special Issue Advanced Photonic Sensing and Measurement)

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9 pages, 3267 KiB

Open AccessArticle

Revealing the Evolution from Q-Switching to Mode-Locking in an Erbium-Doped Fiber Laser Using Tungsten Trioxide Saturable Absorber

by Xin Tan, Ya Liu, Yongkang Zheng, Zewu Xie and Guoqing Hu

Photonics 2022, 9(12), 962; https://doi.org/10.3390/photonics9120962 - 10 Dec 2022

Cited by 4 | Viewed by 3501

Abstract

Passively Q-switching and mode-locking technologies can generate short pulses with durations that differ by several orders of magnitude widely used in different applications. Recently, Q-switching and mode-locking realized in an identical laser cavity with saturable absorbers was reported. The analysis of pulse conversion [...] Read more.

Passively Q-switching and mode-locking technologies can generate short pulses with durations that differ by several orders of magnitude widely used in different applications. Recently, Q-switching and mode-locking realized in an identical laser cavity with saturable absorbers was reported. The analysis of pulse conversion is helpful for us to further understand the pulse dynamics of a laser. In this paper, the pulse evolution from Q-switching, Q-switched mode-locking to mode-locking, is demonstrated by using a tungsten trioxide saturable absorber in a ring-cavity erbium-doped fiber laser. Firstly, self-started Q-switching at 1563 nm is observed, the repetition rate continuously increases, and the duration decreases when the pump power increased. Then, with an adjusting intra-cavity state of polarization under a high pump power level, stable Q-switched mode-locking pulses evolved from Q-switching, are observed. The amplitude of the emerged pulse sequence with a period of 36.8 ns, determined by cavity length, is modulated by the Q-switched envelope with the period of 10.3 μs. By optimizing the intracavity polarization carefully, stable continuous wave mode-locking operation is achieved eventually. To the best of our knowledge, this is the first experimental demonstration of Q-switching and mode-locking, respectively, in an identical transition-metal-oxides-based pulsed fiber laser without modification of cavity structure. Full article

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12 pages, 24525 KiB

Open AccessCommunication

Eight-Wavelength-Switchable Narrow Linewidth Erbium-Doped Fiber Laser Based on Cascaded Superimposed High-Birefringence Fiber Bragg Grating

by Dongyuan Li, Ting Feng, Weiwei Sun, Shengbao Wu, Fengping Yan, Qi Li and Xiaotian Steve Yao

Electronics 2022, 11(22), 3688; https://doi.org/10.3390/electronics11223688 - 10 Nov 2022

Cited by 7 | Viewed by 2222

Abstract

A narrow-linewidth eight-wavelength-switchable erbium-doped fiber laser is proposed, and its performance is demonstrated. A cascaded superimposed high-birefringence fiber Bragg grating is used to determine the lasing wavelengths. The combination of a Fabry–Pérot filter and a single-coupler ring is adopted to achieve the single-longitudinal-mode [...] Read more.

A narrow-linewidth eight-wavelength-switchable erbium-doped fiber laser is proposed, and its performance is demonstrated. A cascaded superimposed high-birefringence fiber Bragg grating is used to determine the lasing wavelengths. The combination of a Fabry–Pérot filter and a single-coupler ring is adopted to achieve the single-longitudinal-mode (SLM) oscillation. By introducing the enhanced polarization-hole-burning effect to suppress the gain competition between different wavelength lasers, the stable lasing output is guaranteed. When the pump power is 200 mW, by adjusting the polarization controller to balance the gain and loss in the laser cavity, 24 switchable lasing modes are achieved, including 8 single-wavelength operations and 16 dual-wavelength operations with orthogonal polarization states. For single-wavelength operations, every laser is in the SLM lasing state, with a high stabilized optical spectrum, a linewidth of approximately 1 kHz, an optical signal-to-noise ratio (OSNR) as high as 73 dB, a relative intensity noise of less than −150 dB/Hz, and very good polarization characteristics. For dual-wavelength operations, the lasers also have a stable spectrum and an OSNR as high as 65 dB. The proposed fiber laser has a wide range of applications, including long-haul coherence optical communication, optical fiber sensing, and dense wavelength-division-multiplexing. Full article

(This article belongs to the Special Issue Optical Fiber Communications: Innovations and Challenges)

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15 pages, 2977 KiB

Open AccessArticle

Highly Stable Switchable Emissions of an Erbium-Doped Fiber Ring Laser Using Cascaded MZIs Based on CHCF

by Luis A. Herrera-Piad, Sigifredo Marrujo-García, Iván Hernández-Romano, Daniel A. May-Arrioja, Vladimir P. Minkovich and Miguel Torres-Cisneros

Machines 2022, 10(10), 962; https://doi.org/10.3390/machines10100962 - 21 Oct 2022

Cited by 3 | Viewed by 1896

Abstract

A stable, single, and dual-wavelength erbium-doped fiber laser (EDFL), based on two Mach–Zehnder interferometers (MZIs), arranged in a cascade configuration, was proposed for experimental purposes. Both MZIs were assembled by splicing a capillary hollow-core fiber (CHCF) section between two multimode fibers (MMFs) segments. [...] Read more.

A stable, single, and dual-wavelength erbium-doped fiber laser (EDFL), based on two Mach–Zehnder interferometers (MZIs), arranged in a cascade configuration, was proposed for experimental purposes. Both MZIs were assembled by splicing a capillary hollow-core fiber (CHCF) section between two multimode fibers (MMFs) segments. The novelty of this single and dual-wavelength EDFL is that the switchable operation of the laser is achieved by thermally tuning the interference pattern of one MZI and not by adjusting the polarization state inside the fiber ring cavity. The maximum measured value of SNR was 58.9 dB for the single and dual-wavelength laser emissions. Moreover, the stable output power exhibited by this EDFL, in terms of minimal power and wavelength fluctuations, at 0.05 dB and 10 pm, was detected during the single and dual-wavelength operation. It is worth noticing that switching is achieved at exact wavelength locations with a separation of 1.8 nm and not randomly, as reported by other works. These features make this switchable EDFL an appealing candidate for application in optical fiber communication systems and fiber sensing. Full article

(This article belongs to the Special Issue Advances in New Laser Devices and Technologies)

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15 pages, 4732 KiB

Open AccessArticle

Narrow Linewidth Half-Open-Cavity Random Laser Assisted by a Three-Grating Ring Resonator for Strain Detection

by Bing Lv, Wentao Zhang, Wenzhu Huang, Fang Li and Yongqian Li

Sensors 2022, 22(20), 7882; https://doi.org/10.3390/s22207882 - 17 Oct 2022

Cited by 7 | Viewed by 2483

Abstract

A stabilized narrow-linewidth random fiber laser for strain detection, based on a three-grating ring (TGR) resonator and half-open-cavity structure, is proposed and investigated experimentally. The half-open-cavity structure proved to provide double optical gain of erbium-doped fiber, which was beneficial to increase the photon [...] Read more.

A stabilized narrow-linewidth random fiber laser for strain detection, based on a three-grating ring (TGR) resonator and half-open-cavity structure, is proposed and investigated experimentally. The half-open-cavity structure proved to provide double optical gain of erbium-doped fiber, which was beneficial to increase the photon lifetime as well as further narrow the linewidth. Meanwhile, the stability and frequency noise of narrow lasing output was improved by suppressing the competition-induced undesired residual random lasing modes with the TGR resonator. The TGR resonator is composed of a double-cavity fiber Bragg grating Fabry–Perot (FBG-FP) interferometer, a section of single-mode fiber, and a circulator. The specially designed double-cavity FBG-FP interferometer embedded in the TGR resonator acted as the strain-sensing element and improved the resolution of the dynamic strain. A stable ultra-narrow linewidth of about 205 Hz was obtained. The frequency noise was reduced to about 2 Hz/√Hz. A high dynamic strain measuring resolution of 35 femto-strain (fε)/√Hz was achieved. Full article

(This article belongs to the Special Issue Fiber Grating Sensors: Design, Fabrication, and Application)

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14 pages, 4039 KiB

Open AccessArticle

Tunable and Switchable Dual-Wavelength SLM Narrow-Linewidth Fiber Laser with a PMFBG-FP Filter Cascaded by Multi-Ring Cavity

by Mingquan Gao, Bin Yin, Yanzhi Lv, Guofeng Sang, Benran Hou, Haisu Li, Muguang Wang and Songhua Wu

Photonics 2022, 9(10), 756; https://doi.org/10.3390/photonics9100756 - 12 Oct 2022

Cited by 19 | Viewed by 2877

Abstract

A single longitudinal mode (SLM) dual-wavelength switchable erbium-doped fiber laser (DW-EDFL) based on polarization-maintaining fiber Bragg grating Fabry–Perot cavity (PMFBG-FP) cascaded multiple sub-ring cavities (MSCs) is proposed. A PMFBG-FP with a narrow-band transmission peak and MSCs was implemented as an optical filter to [...] Read more.

A single longitudinal mode (SLM) dual-wavelength switchable erbium-doped fiber laser (DW-EDFL) based on polarization-maintaining fiber Bragg grating Fabry–Perot cavity (PMFBG-FP) cascaded multiple sub-ring cavities (MSCs) is proposed. A PMFBG-FP with a narrow-band transmission peak and MSCs was implemented as an optical filter to achieve stable dual-wavelength laser output and guaranteed SLM status. By stretching the PMFBG, a highly stable dual-wavelength tunable output could be achieved with a maximum tuning interval of 0.17 nm. The optical signal-to-noise-ratio (OSNR) at dual-wavelength lasing was higher than 57 dB, and the optimal wavelength and power fluctuations within 0.5 h were 0.01 nm and 0.79 dB, respectively. Meanwhile, the measured linewidths of each wavelength were 1.55 kHz and 1.65 kHz, respectively. The measured polarization states of the two laser wavelengths were linear and orthogonal, with a degree of polarization (DOP) of nearly 100%. Full article

(This article belongs to the Section Lasers, Light Sources and Sensors)

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