Pub Date : 2025-02-05DOI: 10.1016/j.yofte.2025.104154
Piotr Bojęś , Yingchu Xu , Wonkeun Chang , Karol Krzempek
We demonstrate a dissipative soliton mode-locked fiber laser with controllable multipulsing. The laser was constructed in a figure-8, nonlinear amplifying loop mirror, all-in fiber cavity configuration using polarization maintaining fibers and components and a 2-meter long PM double-clad active fiber as the gain medium. The self-starting configuration was capable of generating between 1 and 25 subnanosecond pulses in a single bunch, at a 4.05 MHz repetition rate. The number of pulses generated in a single bunch was controllable via the pump power delivered to the active fiber. We provide and discuss a theoretical model of the laser, along with an experimental investigation of the pulse splitting and the laser stability. The capability of utilizing the lasers as a seed source for further amplification was experimentally verified, reaching an output power of 2.63 W during the multipulse operation.
{"title":"Controllable multipulsing in a 1 μm dissipative soliton mode-locked laser","authors":"Piotr Bojęś , Yingchu Xu , Wonkeun Chang , Karol Krzempek","doi":"10.1016/j.yofte.2025.104154","DOIUrl":"10.1016/j.yofte.2025.104154","url":null,"abstract":"<div><div>We demonstrate a dissipative soliton mode-locked fiber laser with controllable multipulsing. The laser was constructed in a figure-8, nonlinear amplifying loop mirror, all-in fiber cavity configuration using polarization maintaining fibers and components and a 2-meter long PM double-clad active fiber as the gain medium. The self-starting configuration was capable of generating between 1 and 25 subnanosecond pulses in a single bunch, at a 4.05 MHz repetition rate. The number of pulses generated in a single bunch was controllable via the pump power delivered to the active fiber. We provide and discuss a theoretical model of the laser, along with an experimental investigation of the pulse splitting and the laser stability. The capability of utilizing the lasers as a seed source for further amplification was experimentally verified, reaching an output power of 2.63 W during the multipulse operation.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"91 ","pages":"Article 104154"},"PeriodicalIF":2.6,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143314743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-03DOI: 10.1016/j.yofte.2025.104148
Zhiyang Wang, Ailing Zhang, Pengxiang Chang, Yanmei Shi, Zhen Li
A photonic crystal fiber (PCF)-based SPR biosensor co-modified by Au film, polydopamine (PDA) and Au nanoparticles (AuNps) is proposed. The refractive index(RI) sensitivity of the sensor is enhanced by the coupling between the SPR inspired in the Au film and the localized surface plasmon resonance (LSPR) inspired in AuNps, as well as the high RI of the PDA. The experimental results show that the PCF-Au-PDA-AuNps sensor obtains a high RI sensitivity of 3523.10 nm/RIU in the RI range of 1.335–––1.365, which is 2.07 times of that of the PCF-Au sensor. In addition, in order to bioassay to rabbit IgG, an extra layer of PDA with excellent adhesion and biocompatibility properties is modified on the surface of AuNps to anchor a layer of goat anti-rabbit Immunoglobulin G(IgG). The bio-sensitivity of the sensor for rabbit IgG reaches 0.951 nm/(µg/mL), and the limit of detection (LOD) is 0.021 µg/mL. Due to its good biosensing performance, this fiber-optic biosensor based on SPR-LSPR coupling is suitable to be applied in clinical disease diagnosis and immunoassay.
{"title":"Sensitivity enhanced SPR/LSPR biosensor based on Au/PDA/AuNps co-modified PCF for rabbit IgG detection","authors":"Zhiyang Wang, Ailing Zhang, Pengxiang Chang, Yanmei Shi, Zhen Li","doi":"10.1016/j.yofte.2025.104148","DOIUrl":"10.1016/j.yofte.2025.104148","url":null,"abstract":"<div><div>A photonic crystal fiber (PCF)-based SPR biosensor co-modified by Au film, polydopamine (PDA) and Au nanoparticles (AuNps) is proposed. The refractive index(RI) sensitivity of the sensor is enhanced by the coupling between the SPR inspired in the Au film and the localized surface plasmon resonance (LSPR) inspired in AuNps, as well as the high RI of the PDA. The experimental results show that the PCF-Au-PDA-AuNps sensor obtains a high RI sensitivity of 3523.10 nm/RIU in the RI range of 1.335–––1.365, which is 2.07 times of that of the PCF-Au sensor. In addition, in order to bioassay to rabbit IgG, an extra layer of PDA with excellent adhesion and biocompatibility properties is modified on the surface of AuNps to anchor a layer of goat anti-rabbit Immunoglobulin G(IgG). The bio-sensitivity of the sensor for rabbit IgG reaches 0.951 nm/(µg/mL), and the limit of detection (LOD) is 0.021 µg/mL. Due to its good biosensing performance, this fiber-optic biosensor based on SPR-LSPR coupling is suitable to be applied in clinical disease diagnosis and immunoassay.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"91 ","pages":"Article 104148"},"PeriodicalIF":2.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143314756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-03DOI: 10.1016/j.yofte.2025.104143
Duc Hoang Trong , Lanh Chu Van , Thuy Nguyen Thi
A novel and simple structure of nitrobenzene-filled hexagonal core photonic crystal fibers with supercontinuum spectral broadening in the mid-infrared region is numerically simulated. We can optimize geometrical parameters such as pitch, larger and smaller air hole diameters, hollow core shape to control and design dispersion characteristics, achieving an all-normal near zero flattened dispersion with fluctuation of ± 1.807 ps/nm·km in the 0.431 µm wavelength range and low value of –2.496 ps/nm·km at the 1.55 µm pump wavelength. The two proposed fibers have small effective mode areas leading to high nonlinear coefficients, with values of 8966.877 and 7311.825 W−1.km−1, respectively, at the pump wavelength of 1.55 µm. At 370 W of pump power, a near-infrared supercontinuum spanning from 0.791 to 2.99 µm with a bandwidth at 30 dB of 1.726 µm is obtained using the first fiber with an all-normal dispersion profile. Soliton dynamics govern the expansion of the supercontinuum spectrum into the mid-infrared region when the second fiber is pumped at a wavelength of 1.55 µm in an anomalous dispersion regime, covering from 0.791 to 6.5 µm (bandwidth of 3.49 µm at 30 dB) with a peak power of 500 W. These numerical results can be useful for various purposes such as biomedical, sensors, and optical coherence tomography.
{"title":"Mid-infrared supercontinuum generation based on hexagonal core silica-photonic crystal fiber with low peak power","authors":"Duc Hoang Trong , Lanh Chu Van , Thuy Nguyen Thi","doi":"10.1016/j.yofte.2025.104143","DOIUrl":"10.1016/j.yofte.2025.104143","url":null,"abstract":"<div><div>A novel and simple structure of nitrobenzene-filled hexagonal core photonic crystal fibers with supercontinuum spectral broadening in the mid-infrared region is numerically simulated. We can optimize geometrical parameters such as pitch, larger and smaller air hole diameters, hollow core shape to control and design dispersion characteristics, achieving an all-normal near zero flattened dispersion with fluctuation of ± 1.807 ps/nm·km in the 0.431 µm wavelength range and low value of –2.496 ps/nm·km at the 1.55 µm pump wavelength. The two proposed fibers have small effective mode areas leading to high nonlinear coefficients, with values of 8966.877 and 7311.825 W<sup>−1</sup>.km<sup>−1</sup>, respectively, at the pump wavelength of 1.55 µm. At 370 W of pump power, a near-infrared supercontinuum spanning from 0.791 to 2.99 µm with a bandwidth at 30 dB of 1.726 µm is obtained using the first fiber with an all-normal dispersion profile. Soliton dynamics govern the expansion of the supercontinuum spectrum into the mid-infrared region when the second fiber is pumped at a wavelength of 1.55 µm in an anomalous dispersion regime, covering from 0.791 to 6.5 µm (bandwidth of 3.49 µm at 30 dB) with a peak power of 500 W. These numerical results can be useful for various purposes such as biomedical, sensors, and optical coherence tomography.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"91 ","pages":"Article 104143"},"PeriodicalIF":2.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143314701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The FBG accelerometer, due to its advantages such as high sensitivity, wide frequency response, immunity to electromagnetic interference, strong corrosion resistance, and miniaturization, has wide applications in engineering fields. Under the premise of ensuring the sensor’s quality factor (Q), this paper introduces an FBG accelerometer featuring a cantilever-hinge structure, which effectively reduces the design and manufacturing complexity of the accelerometer. The accelerometer model is established using vibration theory, with structural optimization and simulation conducted in MATLAB and ANSYS. The accelerometer’s performance was evaluated through experimental testing. The study indicates that the accelerometer’s resonance frequency is 510 Hz, with a smooth frequency response between 0.1 Hz and 150 Hz. Its sensitivity is 54.12 pm/g, while the cross-sensitivity is under 9.7 %. This study offers a new approach to optimizing FBG accelerometer design, facilitating its broader engineering applications.
{"title":"Design and experimental Validation of an FBG accelerometer using Cantilever-Hinge structures","authors":"Yingnan Chen , Xinhao Li , Wenhao Xia , Faxiang Zhang , Shaodong Jiang","doi":"10.1016/j.yofte.2025.104156","DOIUrl":"10.1016/j.yofte.2025.104156","url":null,"abstract":"<div><div>The FBG accelerometer, due to its advantages such as high sensitivity, wide frequency response, immunity to electromagnetic interference, strong corrosion resistance, and miniaturization, has wide applications in engineering fields. Under the premise of ensuring the sensor’s quality factor (<em>Q</em>), this paper introduces an FBG accelerometer featuring a cantilever-hinge structure, which effectively reduces the design and manufacturing complexity of the accelerometer. The accelerometer model is established using vibration theory, with structural optimization and simulation conducted in MATLAB and ANSYS. The accelerometer’s performance was evaluated through experimental testing. The study indicates that the accelerometer’s resonance frequency is 510 Hz, with a smooth frequency response between 0.1 Hz and 150 Hz. Its sensitivity is 54.12 pm/g, while the cross-sensitivity is under 9.7 %. This study offers a new approach to optimizing FBG accelerometer design, facilitating its broader engineering applications.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"91 ","pages":"Article 104156"},"PeriodicalIF":2.6,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143314699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01DOI: 10.1016/j.yofte.2025.104145
Lingbo Cai , Xiaoran Ma , Jianlei Wang , Xiaohan Chang , Hongyang Dong , Mingqi Fan , Tianli Feng , Chun Wang
We report a self-pulsing Er-doped fiber laser (EDFL) which can respectively operate in different dynamic mode-locking regimes, including stable fundamental mode-locking (FML), bunched soliton mode-locking (BSML), harmonic mode-locking (HML) and Q-switched mode-locking (QML). The dynamic evolution of FML pulse to BSML pulse and finally to HML pulse shows a directly dependence on pumping power. At the pumping power of 29 mW, the fiber laser delivers the FML pulses with a repetition frequency of 11.64 MHz and pulse duration of 1.09 ps. The further increase of pumping power makes the FML pulse evolves into the BSML pulses with up to 9 sub-pulses. Once the pumping power reaches 210 mW, the 9th-order HML pulse with a pulse duration of 883 fs is realized. Moreover, the HML pulse can go into the QML regime by adjusting the intracavity polarization state, and the energy of pulse envelope reaches up to 344 nJ at the pumping power of 483 mW. To our best of knowledge, this is the first realization of BSML pulse, femtosecond HML pulse and >300 nJ pulse envelope in a self-pulsing EDFL.
{"title":"Realization of femtosecond harmonic pulse and high-energy pulse envelope in a self-pulsing fiber laser","authors":"Lingbo Cai , Xiaoran Ma , Jianlei Wang , Xiaohan Chang , Hongyang Dong , Mingqi Fan , Tianli Feng , Chun Wang","doi":"10.1016/j.yofte.2025.104145","DOIUrl":"10.1016/j.yofte.2025.104145","url":null,"abstract":"<div><div>We report a self-pulsing Er-doped fiber laser (EDFL) which can respectively operate in different dynamic mode-locking regimes, including stable fundamental mode-locking (FML), bunched soliton mode-locking (BSML), harmonic mode-locking (HML) and Q-switched mode-locking (QML). The dynamic evolution of FML pulse to BSML pulse and finally to HML pulse shows a directly dependence on pumping power. At the pumping power of 29 mW, the fiber laser delivers the FML pulses with a repetition frequency of 11.64 MHz and pulse duration of 1.09 ps. The further increase of pumping power makes the FML pulse evolves into the BSML pulses with up to 9 sub-pulses. Once the pumping power reaches 210 mW, the 9th-order HML pulse with a pulse duration of 883 fs is realized. Moreover, the HML pulse can go into the QML regime by adjusting the intracavity polarization state, and the energy of pulse envelope reaches up to 344 nJ at the pumping power of 483 mW. To our best of knowledge, this is the first realization of BSML pulse, femtosecond HML pulse and >300 nJ pulse envelope in a self-pulsing EDFL.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"91 ","pages":"Article 104145"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143314700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-30DOI: 10.1016/j.yofte.2025.104139
Siti Asma Che Aziz , Norita Mohd Yusoff , Nadiah Husseini Zainol Abidin , Mohammed Thamer Alresheedi , Eng Khoon Ng , Mohd Adzir Mahdi
We demonstrate a sandwich-type saturable absorber (SA) configuration of sub-micron nickel (Ni) particles aimed at generating Q-switched pulses in an erbium-doped fibre laser. The Ni-SA was fabricated by depositing the Ni materials in between two fibre ferrules with 2.38% modulation depth and 225 MW/cm2 saturation intensity. The integration of the Ni-SA in a ring cavity laser generated Q-switched pulses at around 1559 nm lasing wavelength. The pulse operation regime was obtained within 70–250 mW pump power, in which the pulse width and repetition rate were tuneable from 13.98 to 5.12 µs and 25.74 to 55.72 kHz, respectively. Meanwhile, the maximum achievable output power and pulse energy at 250 mW were up to 5.55 mW and 99.71 nJ, respectively. This work unlocks new possibilities of generating high energy microsecond pulses for valuable applications in the near future.
{"title":"Q-switched erbium-doped fibre laser via sub-micron nickel particles saturable absorber","authors":"Siti Asma Che Aziz , Norita Mohd Yusoff , Nadiah Husseini Zainol Abidin , Mohammed Thamer Alresheedi , Eng Khoon Ng , Mohd Adzir Mahdi","doi":"10.1016/j.yofte.2025.104139","DOIUrl":"10.1016/j.yofte.2025.104139","url":null,"abstract":"<div><div>We demonstrate a sandwich-type saturable absorber (SA) configuration of sub-micron nickel (Ni) particles aimed at generating Q-switched pulses in an erbium-doped fibre laser. The Ni-SA was fabricated by depositing the Ni materials in between two fibre ferrules with 2.38% modulation depth and 225 MW/cm<sup>2</sup> saturation intensity. The integration of the Ni-SA in a ring cavity laser generated Q-switched pulses at around 1559 nm lasing wavelength. The pulse operation regime was obtained within 70–250 mW pump power, in which the pulse width and repetition rate were tuneable from 13.98 to 5.12 µs and 25.74 to 55.72 kHz, respectively. Meanwhile, the maximum achievable output power and pulse energy at 250 mW were up to 5.55 mW and 99.71 nJ, respectively. This work unlocks new possibilities of generating high energy microsecond pulses for valuable applications in the near future.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"90 ","pages":"Article 104139"},"PeriodicalIF":2.6,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143129105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-29DOI: 10.1016/j.yofte.2025.104126
Cuiling Zhang , Jose Enrique Antonio-Lopez , Rodrigo Amezcua-Correa , Yazhou Wang , Christos Markos
The anti-resonant hollow-core fiber (ARHCF) lasers in the near-infrared (NIR) and mid-infrared (MIR) spectral domain show a great potential for spectroscopy and high-resolution gas detection. In this work, we demonstrated the generation of a frequency-comb-like Raman laser with high pulse energy spanning from ultraviolet (UV) (328 nm) to NIR (2065 nm wavelength) based on a hydrogen (H2)-filled 7-ring ARHCF. The H2-filled ARHCF is pumped with a custom-laser at 1044 nm with ∼ 75 μJ pulse energy and ∼ 3.7 ns pulse duration. Through stimulated Raman scattering process, we employed the sixth-order rotational Raman Stokes located at ∼ 1650 nm as a case example to demonstrate how the developed high-energy and narrow-linewidth laser source can effectively be used to detect CH4 in the NIR-II region using the photoacoustic modality. We reported the efficient detection of CH4 with sensitivity as low as ∼ 550 ppb with an integration time of ∼ 40 s. In conclusion, the main goal of this work is to demonstrate and emphasize the potential of the gas-filled ARHCF laser technology for compact next-generation spectroscopy across different spectral regions.
{"title":"Photoacoustic methane detection assisted by a H2-filled anti-resonant hollow-core fiber laser","authors":"Cuiling Zhang , Jose Enrique Antonio-Lopez , Rodrigo Amezcua-Correa , Yazhou Wang , Christos Markos","doi":"10.1016/j.yofte.2025.104126","DOIUrl":"10.1016/j.yofte.2025.104126","url":null,"abstract":"<div><div>The anti-resonant hollow-core fiber (ARHCF) lasers in the near-infrared (NIR) and mid-infrared (MIR) spectral domain show a great potential for spectroscopy and high-resolution gas detection. In this work, we demonstrated the generation of a frequency-comb-like Raman laser with high pulse energy spanning from ultraviolet (UV) (328 nm) to NIR (2065 nm wavelength) based on a hydrogen (H<sub>2</sub>)-filled 7-ring ARHCF. The H<sub>2</sub>-filled ARHCF is pumped with a custom-laser at 1044 nm with ∼ 75 μJ pulse energy and ∼ 3.7 ns pulse duration. Through stimulated Raman scattering process, we employed the sixth-order rotational Raman Stokes located at ∼ 1650 nm as a case example to demonstrate how the developed high-energy and narrow-linewidth laser source can effectively be used to detect CH<sub>4</sub> in the NIR-II region using the photoacoustic modality. We reported the efficient detection of CH<sub>4</sub> with sensitivity as low as ∼ 550 ppb with an integration time of ∼ 40 s. In conclusion, the main goal of this work is to demonstrate and emphasize the potential of the gas-filled ARHCF laser technology for compact next-generation spectroscopy across different spectral regions.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"90 ","pages":"Article 104126"},"PeriodicalIF":2.6,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143129103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-28DOI: 10.1016/j.yofte.2025.104150
Yutong Qi , Jinze Li , Yuxin Chen , Bao Zhu , Xingchen Zhou , Xuefei Xiao , Zheyuan Gu , Jun Qian , Chuanyang He , Min Lai , Yan Ma , Bo Liu
A differential fiber optic humidity sensor based on superhydrophilic SiO2/polyethylene glycol (PEG) composite film is presented. With exposure to humid air, the physical properties of SiO2/PEG composite film coated on the sensing region changes, disturbing transmission of evanescent wave of fiber and leading to change of the output light intensity of sensing fiber. The output light intensity of humidity sensor increases with the increase of relative humidity (RH), which is attributed to the expansion of polymeric film and less scattering of light. The sensor shows a linear response of the ratio of output light intensity of sensing fiber to that of reference fiber IS/IR to RH with a correlation coefficient of 0.991 in the range of 11–81 %RH. The ratio IS/IR is independent of the intensity of optical source, indicating that differential sensor structure enables humidity testing immune to instability of light source. In addition, the sensor possesses excellent reversibility, stability and repeatability.
{"title":"Differential fiber optic humidity sensor based on superhydrophilic SiO2/polyethylene glycol composite film with linear response","authors":"Yutong Qi , Jinze Li , Yuxin Chen , Bao Zhu , Xingchen Zhou , Xuefei Xiao , Zheyuan Gu , Jun Qian , Chuanyang He , Min Lai , Yan Ma , Bo Liu","doi":"10.1016/j.yofte.2025.104150","DOIUrl":"10.1016/j.yofte.2025.104150","url":null,"abstract":"<div><div>A differential fiber optic humidity sensor based on superhydrophilic SiO<sub>2</sub>/polyethylene glycol (PEG) composite film is presented. With exposure to humid air, the physical properties of SiO<sub>2</sub>/PEG composite film coated on the sensing region changes, disturbing transmission of evanescent wave of fiber and leading to change of the output light intensity of sensing fiber. The output light intensity of humidity sensor increases with the increase of relative humidity (RH), which is attributed to the expansion of polymeric film and less scattering of light. The sensor shows a linear response of the ratio of output light intensity of sensing fiber to that of reference fiber <em>I</em><sub>S</sub>/<em>I</em><sub>R</sub> to RH with a correlation coefficient of 0.991 in the range of 11–81 %RH. The ratio <em>I</em><sub>S</sub>/<em>I</em><sub>R</sub> is independent of the intensity of optical source, indicating that differential sensor structure enables humidity testing immune to instability of light source. In addition, the sensor possesses excellent reversibility, stability and repeatability.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"90 ","pages":"Article 104150"},"PeriodicalIF":2.6,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143129102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A flexible fiber laser mode-selected by a microfiber knot resonator (MKR) functionalized with 2D planar-shaped graphene-oxide (GO)-MoS2 composite film (GMCF) is proposed and demonstrated. As far as we know, this is the first report of using novel transferring method for forming 2D planar-shaped GMCF on a low-loss MKR for mode-selection in fiber ring cavity. The 2D GMCF is formed on the surface of MKR with high stability due to effects of surface tension and recirculation flow. Mode-locked fiber laser operation with single-wavelength output is realized by saturable absorption effect of the GMCF. The pulse period and repetition frequency are 118.14 ns and 8.464 MHz, respectively. In addition, single-wavelength, tunable lasing using the GMCF-MKR as narrow-bandwidth filter is achieved with a side-mode suppression ratio of 53 dB, a 3 dB bandwidth of < 0.02 dB and a wavelength tuning range from 1551.6 nm to 1552.6 nm. The proposed flexible fiber laser using the 2D planar-shaped GMCF-MKR will have a wide range of applications in the fields of distributed fiber sensing, laser coherent communication and optical precision measurement.
{"title":"Mode-selection of a fiber laser using a microfiber knot resonator functionalized with 2D planar-shaped GO-MoS2 film","authors":"Xinyu Chen, Jiale Xie, Hongdan Wan, Zijia Zhou, Xueying Lin, Jingli Wang, Taoping Hu","doi":"10.1016/j.yofte.2025.104142","DOIUrl":"10.1016/j.yofte.2025.104142","url":null,"abstract":"<div><div>A flexible fiber laser mode-selected by a microfiber knot resonator (MKR) functionalized with 2D planar-shaped graphene-oxide (GO)-MoS<sub>2</sub> composite film (GMCF) is proposed and demonstrated. As far as we know, this is the first report of using novel transferring method for forming 2D planar-shaped GMCF on a low-loss MKR for mode-selection in fiber ring cavity. The 2D GMCF is formed on the surface of MKR with high stability due to effects of surface tension and recirculation flow. Mode-locked fiber laser operation with single-wavelength output is realized by saturable absorption effect of the GMCF. The pulse period and repetition frequency are 118.14 ns and 8.464 MHz, respectively. In addition, single-wavelength, tunable lasing using the GMCF-MKR as narrow-bandwidth filter is achieved with a side-mode suppression ratio of 53 dB, a 3 dB bandwidth of < 0.02 dB and a wavelength tuning range from 1551.6 nm to 1552.6 nm. The proposed flexible fiber laser using the 2D planar-shaped GMCF-MKR will have a wide range of applications in the fields of distributed fiber sensing, laser coherent communication and optical precision measurement.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"90 ","pages":"Article 104142"},"PeriodicalIF":2.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143129101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present a strategy to enhance spatial resolution in Brillouin optical correlation-domain reflectometry (BOCDR) using perfluorinated graded-index polymer optical fibers (POFs). By exploiting the relationship between modulation amplitude and sensing fiber length, we achieve a theoretical spatial resolution of approximately 4.8 cm, surpassing previous limitations. This is accomplished by increasing the modulation amplitude beyond the conventional limit through reduction of the fiber length relative to the measurement range. We validate our approach with preliminary experiments and demonstrate distributed temperature sensing with high spatial resolution, successfully detecting a cooled section as short as 7.0 cm.
{"title":"High-resolution distributed temperature sensing along polymer optical fiber using Brillouin optical correlation-domain reflectometry","authors":"Seiga Ochi , Keita Kikuchi , Shuto Tsurugai , Heeyoung Lee , Yosuke Mizuno","doi":"10.1016/j.yofte.2025.104144","DOIUrl":"10.1016/j.yofte.2025.104144","url":null,"abstract":"<div><div>We present a strategy to enhance spatial resolution in Brillouin optical correlation-domain reflectometry (BOCDR) using perfluorinated graded-index polymer optical fibers (POFs). By exploiting the relationship between modulation amplitude and sensing fiber length, we achieve a theoretical spatial resolution of approximately 4.8 cm, surpassing previous limitations. This is accomplished by increasing the modulation amplitude beyond the conventional limit through reduction of the fiber length relative to the measurement range. We validate our approach with preliminary experiments and demonstrate distributed temperature sensing with high spatial resolution, successfully detecting a cooled section as short as 7.0 cm.</div></div>","PeriodicalId":19663,"journal":{"name":"Optical Fiber Technology","volume":"90 ","pages":"Article 104144"},"PeriodicalIF":2.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143129579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}