The Experts below are selected from a list of 4374 Experts worldwide ranked by ideXlab platform
Gerald Farrell - One of the best experts on this subject based on the ideXlab platform.
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photonic crystal fiber half taper probe based Refractometer
Optics Letters, 2014Co-Authors: Pengfei Wang, Yuliya Semenova, Ming Ding, Li O, Chunying Gua, Libo Yua, Gilberto Ambilla, Gerald FarrellAbstract:A compact singlemode - photonic crystal fiber - singlemode fiber tip (SPST) refractive index sensor is demonstrated in this paper. A CO2 laser cleaving technique is utilised to provide a clean-cut fiber tip which is then coated by a layer of gold to increase reflection. An average sensitivity of 39.1 nm/RIU and a resolvable index change of 2.56 x 10-4 are obtained experimentally with a ~3.2 µm diameter SPST. The temperature dependence of this fiber optic sensor probe is presented. The proposed SPST Refractometer is also significantly less sensitive to temperature and an experimental demonstration of this reduced sensitivity is presented in the paper. Because of its compactness, ease of fabrication, linear response, low temperature dependency, easy connectivity to other fiberized optical components and low cost, this Refractometer could find various applications in chemical and biological sensing.
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low temperature sensitivity periodically tapered photonic crystal fiber based Refractometer
Optics Letters, 2013Co-Authors: Pengfei Wang, Yuliya Semenova, Li O, Chunying Gua, Gilberto Ambilla, Gerald FarrellAbstract:In this Letter, an all-fiber Refractometer with a simple configuration of periodical tapers on a photonic crystal fiber (PCF) is proposed and investigated experimentally. The proposed fiber refractive index (RI) sensor consists of a PCF sandwiched between two standard single-mode fibers, with tapers periodically fabricated along the PCF using a CO2 laser beam focused by a ZnSe cylindrical lens. The proposed fiber sensor can be used for RI sensing by measuring the wavelength shift of the multimode interference dip over the transmission spectrum. An average sensitivity of 222 nm/RIU has been experimentally achieved over a RI range from 1.33 to 1.38. The proposed Refractometer is also significantly less sensitive to temperature, and an experimental demonstration of this reduced sensitivity is presented. The proposed RI sensor benefits from simplicity and low-cost and achieves a competitive sensitivity compared with other existing fiber-optic sensors.
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a comprehensive analysis verified by experiment of a Refractometer based on an smf28 small core singlemode fiber scsmf smf28 fiber structure
Journal of Optics, 2011Co-Authors: Yuliya Semenova, Pengfei Wang, Gerald FarrellAbstract:A comprehensive theoretical model for an SMF28–small-core SMF (SCSMF)–SMF28 structure based Refractometer is developed based on the modal propagation analysis (MPA) method. The simulation result shows that the wavelength shift of this Refractometer changes exponentially as the surrounding refractive index (SRI) varies. The core diameter of SCSMF does not have a significant influence on the sensitivity of the Refractometer but cladding diameter does have. The simulation results are verified experimentally and it is also experimentally demonstrated that there is a maximum sensitivity of 1808 nm/RIU (refractive index unit) for an SRI range from 1.324 to 1.431 and that, as expected, the wavelength shift response is an exponential function of SRI.
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high sensitivity evanescent field refractometric sensor based on a tapered multimode fiber interference
Optics Letters, 2011Co-Authors: Pengfei Wang, Yuliya Semenova, Qiang Wu, Ming Ding, Gilberto Brambilla, Gerald FarrellAbstract:We propose and experimentally demonstrate an enhanced evanescent field fiber Refractometer based on a tapered multimode fiber sandwiched between two single-mode fibers. Experiments show that this fiber sensor offers ultrahigh sensitivity [better than 1900nm/RIU at a refractive index (RI) of 1.44] for RI measurements within the range of 1.33 to 1.44, in agreement with the theoretical predictions. This is the highest value reported to date (to our knowledge) in the literature
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high sensitivity sms fiber structure based Refractometer analysis and experiment
Optics Express, 2011Co-Authors: Qiang Wu, Pengfei Wang, Yuliya Semenova, Gerald FarrellAbstract:We have investigated the influence of multimode fiber core (MMFC) diameters and lengths on the sensitivity of an SMS fiber based Refractometer. We show that the MMFC diameter has significant influence on the refractive index (RI) sensitivity but the length does not. A Refractometer with a lower MMFC diameter has a higher sensitivity. Experimental investigations achieved a maximum sensitivity of 1815 nm/ RIU (refractive index unit) for a refractive index range from 1.342 to 1.437 for a Refractometer with a core diameter of 80 μm. The experimental results fit well with the numerical simulation results.
Pengfei Wang - One of the best experts on this subject based on the ideXlab platform.
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photonic crystal fiber half taper probe based Refractometer
Optics Letters, 2014Co-Authors: Pengfei Wang, Yuliya Semenova, Ming Ding, Li O, Chunying Gua, Libo Yua, Gilberto Ambilla, Gerald FarrellAbstract:A compact singlemode - photonic crystal fiber - singlemode fiber tip (SPST) refractive index sensor is demonstrated in this paper. A CO2 laser cleaving technique is utilised to provide a clean-cut fiber tip which is then coated by a layer of gold to increase reflection. An average sensitivity of 39.1 nm/RIU and a resolvable index change of 2.56 x 10-4 are obtained experimentally with a ~3.2 µm diameter SPST. The temperature dependence of this fiber optic sensor probe is presented. The proposed SPST Refractometer is also significantly less sensitive to temperature and an experimental demonstration of this reduced sensitivity is presented in the paper. Because of its compactness, ease of fabrication, linear response, low temperature dependency, easy connectivity to other fiberized optical components and low cost, this Refractometer could find various applications in chemical and biological sensing.
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low temperature sensitivity periodically tapered photonic crystal fiber based Refractometer
Optics Letters, 2013Co-Authors: Pengfei Wang, Yuliya Semenova, Li O, Chunying Gua, Gilberto Ambilla, Gerald FarrellAbstract:In this Letter, an all-fiber Refractometer with a simple configuration of periodical tapers on a photonic crystal fiber (PCF) is proposed and investigated experimentally. The proposed fiber refractive index (RI) sensor consists of a PCF sandwiched between two standard single-mode fibers, with tapers periodically fabricated along the PCF using a CO2 laser beam focused by a ZnSe cylindrical lens. The proposed fiber sensor can be used for RI sensing by measuring the wavelength shift of the multimode interference dip over the transmission spectrum. An average sensitivity of 222 nm/RIU has been experimentally achieved over a RI range from 1.33 to 1.38. The proposed Refractometer is also significantly less sensitive to temperature, and an experimental demonstration of this reduced sensitivity is presented. The proposed RI sensor benefits from simplicity and low-cost and achieves a competitive sensitivity compared with other existing fiber-optic sensors.
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a comprehensive analysis verified by experiment of a Refractometer based on an smf28 small core singlemode fiber scsmf smf28 fiber structure
Journal of Optics, 2011Co-Authors: Yuliya Semenova, Pengfei Wang, Gerald FarrellAbstract:A comprehensive theoretical model for an SMF28–small-core SMF (SCSMF)–SMF28 structure based Refractometer is developed based on the modal propagation analysis (MPA) method. The simulation result shows that the wavelength shift of this Refractometer changes exponentially as the surrounding refractive index (SRI) varies. The core diameter of SCSMF does not have a significant influence on the sensitivity of the Refractometer but cladding diameter does have. The simulation results are verified experimentally and it is also experimentally demonstrated that there is a maximum sensitivity of 1808 nm/RIU (refractive index unit) for an SRI range from 1.324 to 1.431 and that, as expected, the wavelength shift response is an exponential function of SRI.
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high sensitivity evanescent field refractometric sensor based on a tapered multimode fiber interference
Optics Letters, 2011Co-Authors: Pengfei Wang, Yuliya Semenova, Qiang Wu, Ming Ding, Gilberto Brambilla, Gerald FarrellAbstract:We propose and experimentally demonstrate an enhanced evanescent field fiber Refractometer based on a tapered multimode fiber sandwiched between two single-mode fibers. Experiments show that this fiber sensor offers ultrahigh sensitivity [better than 1900nm/RIU at a refractive index (RI) of 1.44] for RI measurements within the range of 1.33 to 1.44, in agreement with the theoretical predictions. This is the highest value reported to date (to our knowledge) in the literature
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high sensitivity sms fiber structure based Refractometer analysis and experiment
Optics Express, 2011Co-Authors: Qiang Wu, Pengfei Wang, Yuliya Semenova, Gerald FarrellAbstract:We have investigated the influence of multimode fiber core (MMFC) diameters and lengths on the sensitivity of an SMS fiber based Refractometer. We show that the MMFC diameter has significant influence on the refractive index (RI) sensitivity but the length does not. A Refractometer with a lower MMFC diameter has a higher sensitivity. Experimental investigations achieved a maximum sensitivity of 1815 nm/ RIU (refractive index unit) for a refractive index range from 1.342 to 1.437 for a Refractometer with a core diameter of 80 μm. The experimental results fit well with the numerical simulation results.
Yuliya Semenova - One of the best experts on this subject based on the ideXlab platform.
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photonic crystal fiber half taper probe based Refractometer
Optics Letters, 2014Co-Authors: Pengfei Wang, Yuliya Semenova, Ming Ding, Li O, Chunying Gua, Libo Yua, Gilberto Ambilla, Gerald FarrellAbstract:A compact singlemode - photonic crystal fiber - singlemode fiber tip (SPST) refractive index sensor is demonstrated in this paper. A CO2 laser cleaving technique is utilised to provide a clean-cut fiber tip which is then coated by a layer of gold to increase reflection. An average sensitivity of 39.1 nm/RIU and a resolvable index change of 2.56 x 10-4 are obtained experimentally with a ~3.2 µm diameter SPST. The temperature dependence of this fiber optic sensor probe is presented. The proposed SPST Refractometer is also significantly less sensitive to temperature and an experimental demonstration of this reduced sensitivity is presented in the paper. Because of its compactness, ease of fabrication, linear response, low temperature dependency, easy connectivity to other fiberized optical components and low cost, this Refractometer could find various applications in chemical and biological sensing.
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low temperature sensitivity periodically tapered photonic crystal fiber based Refractometer
Optics Letters, 2013Co-Authors: Pengfei Wang, Yuliya Semenova, Li O, Chunying Gua, Gilberto Ambilla, Gerald FarrellAbstract:In this Letter, an all-fiber Refractometer with a simple configuration of periodical tapers on a photonic crystal fiber (PCF) is proposed and investigated experimentally. The proposed fiber refractive index (RI) sensor consists of a PCF sandwiched between two standard single-mode fibers, with tapers periodically fabricated along the PCF using a CO2 laser beam focused by a ZnSe cylindrical lens. The proposed fiber sensor can be used for RI sensing by measuring the wavelength shift of the multimode interference dip over the transmission spectrum. An average sensitivity of 222 nm/RIU has been experimentally achieved over a RI range from 1.33 to 1.38. The proposed Refractometer is also significantly less sensitive to temperature, and an experimental demonstration of this reduced sensitivity is presented. The proposed RI sensor benefits from simplicity and low-cost and achieves a competitive sensitivity compared with other existing fiber-optic sensors.
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a comprehensive analysis verified by experiment of a Refractometer based on an smf28 small core singlemode fiber scsmf smf28 fiber structure
Journal of Optics, 2011Co-Authors: Yuliya Semenova, Pengfei Wang, Gerald FarrellAbstract:A comprehensive theoretical model for an SMF28–small-core SMF (SCSMF)–SMF28 structure based Refractometer is developed based on the modal propagation analysis (MPA) method. The simulation result shows that the wavelength shift of this Refractometer changes exponentially as the surrounding refractive index (SRI) varies. The core diameter of SCSMF does not have a significant influence on the sensitivity of the Refractometer but cladding diameter does have. The simulation results are verified experimentally and it is also experimentally demonstrated that there is a maximum sensitivity of 1808 nm/RIU (refractive index unit) for an SRI range from 1.324 to 1.431 and that, as expected, the wavelength shift response is an exponential function of SRI.
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high sensitivity evanescent field refractometric sensor based on a tapered multimode fiber interference
Optics Letters, 2011Co-Authors: Pengfei Wang, Yuliya Semenova, Qiang Wu, Ming Ding, Gilberto Brambilla, Gerald FarrellAbstract:We propose and experimentally demonstrate an enhanced evanescent field fiber Refractometer based on a tapered multimode fiber sandwiched between two single-mode fibers. Experiments show that this fiber sensor offers ultrahigh sensitivity [better than 1900nm/RIU at a refractive index (RI) of 1.44] for RI measurements within the range of 1.33 to 1.44, in agreement with the theoretical predictions. This is the highest value reported to date (to our knowledge) in the literature
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high sensitivity sms fiber structure based Refractometer analysis and experiment
Optics Express, 2011Co-Authors: Qiang Wu, Pengfei Wang, Yuliya Semenova, Gerald FarrellAbstract:We have investigated the influence of multimode fiber core (MMFC) diameters and lengths on the sensitivity of an SMS fiber based Refractometer. We show that the MMFC diameter has significant influence on the refractive index (RI) sensitivity but the length does not. A Refractometer with a lower MMFC diameter has a higher sensitivity. Experimental investigations achieved a maximum sensitivity of 1815 nm/ RIU (refractive index unit) for a refractive index range from 1.342 to 1.437 for a Refractometer with a core diameter of 80 μm. The experimental results fit well with the numerical simulation results.
Xinyong Dong - One of the best experts on this subject based on the ideXlab platform.
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power referenced Refractometer with tilted fiber bragg grating cascaded by chirped grating
Optics Communications, 2014Co-Authors: Xinyong Dong, Jie Zheng, Perry Ping ShumAbstract:Abstract A power-referenced Refractometer operating in reflection mode is proposed and experimentally demonstrated based on a tilted-fiber Bragg grating (TFBG) cascaded by a reflection-band-matched chirped-fiber Bragg grating (CFBG). The optical signal reflected by the CFBG passes twice through the TFBG that enhances sensitivity of the Refractometer. In addition, the optical signal is propagating all the way in the fiber core so that the extra insertion loss is low. Refractive index measurement with sensitivity up to 597.2 μW/R.I.U. is achieved within the range from 1.333 to ~1.42. The maximum detectable refractive index is ~1.45.
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miniature Refractometer based on mach zehnder interferometer with waist enlarged fusion bitaper
Optics Communications, 2013Co-Authors: Chi Chiu Cha, Xinyong Dong, Wenwe QiaAbstract:Abstract A miniature Refractometer by using a Mach–Zehnder interferometer (MZI) in a standard single mode fiber (SMF) with two waist-enlarged fusion bitapers is proposed and experimentally demonstrated. Such an all-fiber SMF-MZI incorporates an intermodal interference between the core mode and cladding modes. Because the cladding modes are sensitive to the external environment, the SMF-MZI is exploited for refractive index measurement. Experimentally, high sensitivity of 266.5 nm/RIU and resolution of 3.75×10−5 RIU are achieved within a range from 1.346 to 1.4412. The temperature effect of the proposed Refractometer is also analyzed.
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temperature independent Refractometer based on a tapered photonic crystal fiber interferometer
Optics Communications, 2013Co-Authors: Chi Chiu Cha, Xinyong Dong, Chueh Loo PohAbstract:Abstract A temperature-independent Refractometer by using a tapered photonic crystal fiber (PCF) based Mach–Zehnder interferometer (MZI) is proposed and experimentally demonstrated. It is fabricated by sandwiching a tapered PCF of 29 mm long between two standard single mode fibers (SMFs) with the fully collapsed air holes of the PCF in the fusion splicing region. It has been found that tapering the PCF greatly enhances the sensitivity of the Refractometer. A maximum sensitivity of 1529 nm/RIU (refractive index unit) is achieved within the range from 1.3355 to 1.413. The Refractometer is nearly temperature-insensitive due to the ultra low temperature dependence of the used.
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miniature Refractometer based on modal interference in a hollow core photonic crystal fiber with collapsed splicing
Journal of Biomedical Optics, 2011Co-Authors: Huaping Gong, Chi Chiu Cha, Yifa Zhang, Wei Chang Wong, Xinyong DongAbstract:A miniature modal interferometer based on a hollow-core photonic crystal fiber (HC-PCF) for refractive index measurement is demonstrated. The modal interferometer is fabricated by splicing the two ends of a 1.2-mm- long HC-PCF to a single-mode fiber (SMF). The air holes of the HC-PCF are fully collapsed by the discharge arc during the splicing procedure, and the length of each collapsed region is about 300 μm. The transmission spectra with different refractive indices outside the HC-PCF are measured. Measurement resolutions of an 8.1×10 −4 refractive index unit (RIU) in the range of 1.35 to 1.39, and 4.3×10 −4 RIU in the range of 1.39 to 1.43 are achieved, respectively. The temperature effect of the proposed Refractometer is also analyzed. C 2011 Society of Photo- In this work, a miniature Refractometer based on modal in- terference in the HC-PCF is demonstrated. A special splicing method is used to produce complete collapse of air holes in the core and cladding of the HC-PCF. Due to the complete collapse effect, this proposed interferometer is highly sensitive to the change of refractive index outside the fiber. The sensor fabri- cation and principle are described. Results and discussion are presented, and a conclusion is given.
Jacques Albe - One of the best experts on this subject based on the ideXlab platform.
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a true fiber optic Refractometer
Laser & Photonics Reviews, 2017Co-Authors: Wenju Zhou, Ya Zhou, Jacques AlbeAbstract:The best instrument to measure the refractive index of liquids is the Abbe Refractometer which can only provide accuracies of the order of 10−5 at visible wavelengths and 10−4 in the near infrared. Here we present a technique by which the exact wavelength positions in the near infrared frequency comb of a tilted grating inscribed in the core of an optical fiber can be used to measure the absolute value of the refractive index of a liquid in which the fiber is inserted, with an accuracy of ±5×10−5. This is in contrast to typical fiber optic-based “refractometry” where only refractive index variations can be measured accurately, hence the appellation of “true” fiber optic Refractometer here. In addition to the increased accuracy, the fiber Refractometer proposed here offers the additional advantages associated with in situ measurements. The performance of this Refractometer is demonstrated by measurements in water from room temperature down to near freezing at wavelengths in the 1550 nm window.
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quasi distributed Refractometer using tilted bragg gratings and time domain reflectometry
Optics Express, 2008Co-Authors: Christophe Caucheteu, Marc Wuilpa, Chengku Che, Patrice Megre, Jacques AlbeAbstract:Tilted fiber Bragg gratings (TFBGs) have been demonstrated to be accurate Refractometers as they couple light from the fiber core to the cladding. Because they require spectral measurements on several tens of nanometers, demodulation techniques reported so far are not suited for quasi-distributed refractive index sensing using TFBGs cascaded along a single optical fiber. We demonstrate here that a commercial Optical Time Domain Reflectometer (OTDR) can be used to multiplex identical TFBGs Refractometers written in the same optical fiber. Our solution is simple, relatively fast, cost-effective and is particularly interesting for the monitoring of long structures.
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power referenced and temperature calibrated optical fiber Refractometer
IEEE Photonics Technology Letters, 2008Co-Authors: Tua Guo, Chengku Che, Albane Laronche, Jacques AlbeAbstract:A novel technique for simultaneous measurement of refractive index and temperature based on power level detection of a weakly tilted fiber Bragg grating (TFBG) is proposed and experimentally demonstrated. Surrounding refractive index (RI) and temperature can be unambiguously determined by the TFBG transmitted and reflected power, respectively, avoiding complex wavelength interrogation. An accuracy approaching 1 x 10-4 in terms of the RI as well as temperature self-calibration is shown for this robust and cost-effective Refractometer.
