In this paper,an efficient 8-channel 32Gbps RoF(Radio over Fiber)system incorporating Bessel Filter(8/32 RoFBF)has been demonstrated to reduce the impact of non-linear transmission effects,specifically Four-Wave Mixin...In this paper,an efficient 8-channel 32Gbps RoF(Radio over Fiber)system incorporating Bessel Filter(8/32 RoFBF)has been demonstrated to reduce the impact of non-linear transmission effects,specifically Four-Wave Mixing(FWM).The simulation results indicate that the proposed 8/32 RoF-BF system provides an optimum result w.r.t.channel spacing(75 GHz),input source power(0 dBm)and number of input channels(8).In comparison with the existing RoF system,the proposed 8/32 RoF-BF system has been validated analytically and it is found that the performance of the proposed system is in close proximity particularly in FWM sideband power reduction of the order of 4 dBm for the 8-channel 32Gbps RoF system.展开更多
<div style="text-align:justify;"> In this paper, a hybrid optical fiber structure for solution concentration measurement with the temperature compensation is proposed. The structure consists of long pe...<div style="text-align:justify;"> In this paper, a hybrid optical fiber structure for solution concentration measurement with the temperature compensation is proposed. The structure consists of long period fiber grating (LPFG) and single mode-multimode-single mode (SMS) fiber structures. The sensing mechanism of the device is studied and verified by experiments. LPFG is sensitive to solution concentration and is affected by temperature crosstalk. SMS structure is not affected by solution concentration, but sensitive to ambient temperature. It can be used as a temperature compensation system. The sensitivity coefficients of LPFG and SMS on temperature and concentration were measured experimentally, and a dual-wavelength matrix was established to realize simultaneous measurement of solution temperature and concentration. </div>展开更多
We present a polarization-maintaining PANDA ring-core fiber(PM-PRCF) characterized by the combination of a ring-core structure with two stress-applying rods. This special fiber design separates the adjacent modes and ...We present a polarization-maintaining PANDA ring-core fiber(PM-PRCF) characterized by the combination of a ring-core structure with two stress-applying rods. This special fiber design separates the adjacent modes and avoids the cutoff of the higher-order modes, which is a common problem in elliptical core polarization-maintaining few-mode fibers. Using a high-contrast index ring and stress-induced birefringence, the PM-PRCF features support for 10 vector modes, with effective refractive index separations from their adjacent modes >10^(-4).Broadband performance is investigated subsequently over a wide wavelength range from 1500 to 1630 nm.The proposed fiber is targeted at applications in space-division multiplexing while eliminating the complex multiple-input multiple-output signal processing.展开更多
Guided modes in a hollow optical fiber are investigated using both scalar approximation and exact vectorial analysis. Effective indices of modes are seen to exhibit "nearly degenerate" groups. Besides provid...Guided modes in a hollow optical fiber are investigated using both scalar approximation and exact vectorial analysis. Effective indices of modes are seen to exhibit "nearly degenerate" groups. Besides providing an insight of modal characteristics, the analysis would prove to be useful to define design parameters for realizing components based on these fibers, and to explore new possibilities.展开更多
We present the investigation on deformation of orbital angular momentum(OAM)modes in bending ring-core fibers(RCFs)with different structure sizes through numerical and experimental studies.The effective refractive ind...We present the investigation on deformation of orbital angular momentum(OAM)modes in bending ring-core fibers(RCFs)with different structure sizes through numerical and experimental studies.The effective refractive index differences of even and odd fiber eigenmodes,which constitute OAM_(±1;1) modes,induced by RCF bending and their impacts on the OAM_(±1;1) mode intensity distributions are analyzed.Bending experiments are also carried out on three different RCFs,and the results match well with simulation values.It is found that RCFs with smaller inner and outer radii show preferable tolerance to the fiber bending.展开更多
An in-fiber Mach-Zehnder interferometer is proposed for the discrimination of strain and temperature.The sensor is based on two cascaded standard single mode fibers using three peanut tapers fabricated by simple splic...An in-fiber Mach-Zehnder interferometer is proposed for the discrimination of strain and temperature.The sensor is based on two cascaded standard single mode fibers using three peanut tapers fabricated by simple splicing.The cascaded structure excites more frequency components,which induce four sets of interference dips in the transmission spectrum.One set of the spectrum dips have different sensitivities to temperature and strain from those of the other three.The sensor can discriminate strain and temperature by monitoring the wavelength shifts of two spectrum dips.Repeated experiments are taken both for strain and temperature increasing and decreasing scenarios.Experimental results show that Dip 1 has an average strain sensitivity of-0.911 pm/με and an average temperature sensitivity of 49.98pm/℃.The strain sensitivity for Dip 2 is negligible and its average temperature sensitivity is 60.52pm/℃.The strain and temperature resolutions are±3.82με and±0.33℃.展开更多
We propose a novel waveguide design of polarization-maintaining few mode fiber(PM-FMF) supporting ≥10non-degenerate modes, utilizing a central circular air hole and a circumjacent elliptical-ring core. The structure ...We propose a novel waveguide design of polarization-maintaining few mode fiber(PM-FMF) supporting ≥10non-degenerate modes, utilizing a central circular air hole and a circumjacent elliptical-ring core. The structure endows a new degree of freedom to adjust the birefringence of all the guided modes, including the fundamental polarization mode. Numerical simulations demonstrate that, by optimizing the air hole and elliptical-ring core,a PM-FMF supporting 10 distinctive polarization modes has been achieved, and the effective index difference Δn_(eff) between the adjacent guided modes could be kept larger than 1.32 × 10^(-4) over the whole C +L band. The proposed fiber structure can flexibly tailored to support an even larger number of modes in PM-FMF(14-mode PM-FMF has been demonstrated as an example), which can be readily applicable to a scalable mode division multiplexing system.展开更多
A Mach-Zehnder interferometer(MZI)for high temperature(1000°C)sensing based on few mode fiber(FMF)was proposed and experimentally demonstrated.The sensor was fabricated by fusing a section of FMF between two sing...A Mach-Zehnder interferometer(MZI)for high temperature(1000°C)sensing based on few mode fiber(FMF)was proposed and experimentally demonstrated.The sensor was fabricated by fusing a section of FMF between two single-mode fibers(SMFs).The structure was proven to be an excellent high temperature sensor with good stability,repeatability,and high temperature sensitivity(48.2 pm/C)after annealing process at a high temperature lasting some hours,and a wide working temperature range(from room temperature to 1000 C).In addition,the simple fabrication process and the low cost offered a great potential for sensing in high temperature environments.展开更多
We propose a low-threshold soliton fiber laser passively mode locked with two different types of film-like saturable absorbers, one of which is fabricated by mixing Bi2Te3 with de-ionized water, as well as polyvinyl a...We propose a low-threshold soliton fiber laser passively mode locked with two different types of film-like saturable absorbers, one of which is fabricated by mixing Bi2Te3 with de-ionized water, as well as polyvinyl alcohol(PVA), and then evaporating them in a Petri dish, and the other of which is prepared by directly dropping Bi2Te3 solution on the PVA film. Both Bi2Te3–PVA films exhibit outstanding features of low loss, high flexibility, and easy synthesis. By incorporating Bi2Te3–PVA films into fiber lasers, stable single-soliton emissions are obtained at a low pump power of 13 mW. Our results suggest that the Bi2Te3 can work as a promising mode locker for ultrafast lasers,while PVA is an excellent host for fabricating high-performance film-based saturable absorbers.展开更多
A refractive index insensitive temperature sensor based on waist-enlarged few mode fiber(FMF) bitapers is presented. The first section of FMF is spliced between two single-mode fibers. In fusion process,the waist-enla...A refractive index insensitive temperature sensor based on waist-enlarged few mode fiber(FMF) bitapers is presented. The first section of FMF is spliced between two single-mode fibers. In fusion process,the waist-enlarged FMF bitapers can be obtained by large current discharging repeatedly. The refractive index and temperature sensing mechanisms are analyzed. For the sensors with different sizes,the refractive index and temperature experiments have been performed. The results show that in the refractive index ranges of 1.335 0—1.346 6 and 1.348 2—1.419 3,the refractive index insensitivity is verified. In a temperature range of 31.9—90 °C,the sensor sensitivity can be up to 85.57 pm/°C. In addition,it has a compact structure. Therefore,the sensor can avoid the cross sensitivity for measuring the refractive index and temperature simultaneously.展开更多
Transverse mode characteristics of a laser are related to a variety of interesting applications. An on-demand mode solid laser in the 1064 nm band was proposed previously. In this paper, we provide a fiber laser for o...Transverse mode characteristics of a laser are related to a variety of interesting applications. An on-demand mode solid laser in the 1064 nm band was proposed previously. In this paper, we provide a fiber laser for on-demand modes in the 1550 nm band to prescribe the pure and high-quality emission of a higher-order transverse laser mode, based on a simple construction with one spatial light modulator(SLM) and a single-mode erbium-doped fiber(SM-EDF). The SLM is designated to generate the desired higher-order mode and separate the higher-order mode and the fundamental mode. The fundamental mode oscillates in the fiber ring laser, and therefore the SM-EDF can be pumped with a single-mode 980 nm laser, no matter what higher-order mode is prescribed.In this proof-of-principle experiment, high-quality higher-order modes are observed from LP01 to LP105.Stable emission and real-time switching between modes can be easily realized by altering the phase on the SLM. In addition, the propagation of the LP_(01), LP_(11), LP_(21), and LP_(02) modes from the fiber laser is also demonstrated in a four-mode few-mode fiber.展开更多
In this paper, we proposed a way to realize an Er-doped random fiber laser(RFL) with a disordered fiber Bragg grating(FBG) array, as well as to control the lasing mode of the RFL by heating specific locations of the d...In this paper, we proposed a way to realize an Er-doped random fiber laser(RFL) with a disordered fiber Bragg grating(FBG) array, as well as to control the lasing mode of the RFL by heating specific locations of the disordered FBG array. The disordered FBG array performs as both the gain medium and random distributed reflectors, which together with a tunable point reflector form the RFL. Coherent multi-mode random lasing is obtained with a threshold of between 7.5 and 10 mW and a power efficiency between 23% and 27% when the reflectivity of the point reflector changes from 4% to 50%. To control the lasing mode of random emission, a specific point of the disordered FBG array is heated so as to shift the wavelength of the FBG(s) at this point away from the other FBGs.Thus, different resonance cavities are formed, and the lasing mode can be controlled by changing the location of the heating point.展开更多
In this paper, we present a mode-selective coupler based on a dual-core all-solid photonic bandgap fiber(AS-PBGF). Because they are all-solid, AS-PBGF-based mode converters are easier to splice to other fibers than ...In this paper, we present a mode-selective coupler based on a dual-core all-solid photonic bandgap fiber(AS-PBGF). Because they are all-solid, AS-PBGF-based mode converters are easier to splice to other fibers than those based on air-hole photonic crystal fibers. Mode conversions between the LP01 and LP11modes, LP01 and LP21modes, and LP01 and LP02modes are obtained at the wavelength λ=1550 nm. The 3 dB wavelength bandwidth of these mode converters are 47.8,20.3, and 20.3 nm, respectively.展开更多
Core mode cutoff is a useful concept not only for a tapered single-core fiber(SCF) but also for a tapered multicore fiber(MCF) to realize cladding mode transmission. In this paper, cut-off conditions of either core mo...Core mode cutoff is a useful concept not only for a tapered single-core fiber(SCF) but also for a tapered multicore fiber(MCF) to realize cladding mode transmission. In this paper, cut-off conditions of either core mode for tapered SCFs or supermodes for MCFs are theoretically investigated. Rigorous analytical formulas are derived for the modes of SCF by a three-layer waveguide model, and an approximation formula of the cut-off condition is given for the LP01 mode. The supermodes of MCFs are analyzed by the coupling mode theory, and the cut-off condition is calculated by a numerical method. Simulation results show that the in-phase supermode of MCFs has a similar cut-off condition with that of SCF. Based on this property, a convenient approximate formula is given to estimate the cut-off condition of the in-phase supermode for tapered MCFs.展开更多
Dispersion compensation with few-mode fibers is emerging as a promising technique that can provide full dispersion and dispersion-slope compensation. The inherent modal path diversity of these fibers allows implementa...Dispersion compensation with few-mode fibers is emerging as a promising technique that can provide full dispersion and dispersion-slope compensation. The inherent modal path diversity of these fibers allows implementation of static as well as tunable dispersion management schemes. In addition, the low non-linearity of this technology can improve system OSNR, leading to enhancements in transmission distances.展开更多
A frequency domain analysis is presented to determine the performance characteristics of a tunable all-optical wavelength converter using four-wave mixing (FWM) in a single mode fiber (SMF) around the zero dispersion ...A frequency domain analysis is presented to determine the performance characteristics of a tunable all-optical wavelength converter using four-wave mixing (FWM) in a single mode fiber (SMF) around the zero dispersion wavelength using two pump lasers. The output converted signal power as well as efficiency evaluated at a bit rate of 10 Gb/s show that the signal power is substantially higher at lower values of wavelength separation.展开更多
Transmission of 40Gbit/s NRZ signal was successfully demonstrated over 219km of installed SMF in KT's Daejeon area network. After transmission, the measured power penalty was 0.5dB for all the tributary channels.
We measured macro-bending losses for two large mode area photonic crystal fibers. Experimental results show that macro-bending loss and loss window are dependent on the parameter d/∧ and number of air-holes ring in t...We measured macro-bending losses for two large mode area photonic crystal fibers. Experimental results show that macro-bending loss and loss window are dependent on the parameter d/∧ and number of air-holes ring in the cladding.展开更多
文摘In this paper,an efficient 8-channel 32Gbps RoF(Radio over Fiber)system incorporating Bessel Filter(8/32 RoFBF)has been demonstrated to reduce the impact of non-linear transmission effects,specifically Four-Wave Mixing(FWM).The simulation results indicate that the proposed 8/32 RoF-BF system provides an optimum result w.r.t.channel spacing(75 GHz),input source power(0 dBm)and number of input channels(8).In comparison with the existing RoF system,the proposed 8/32 RoF-BF system has been validated analytically and it is found that the performance of the proposed system is in close proximity particularly in FWM sideband power reduction of the order of 4 dBm for the 8-channel 32Gbps RoF system.
文摘<div style="text-align:justify;"> In this paper, a hybrid optical fiber structure for solution concentration measurement with the temperature compensation is proposed. The structure consists of long period fiber grating (LPFG) and single mode-multimode-single mode (SMS) fiber structures. The sensing mechanism of the device is studied and verified by experiments. LPFG is sensitive to solution concentration and is affected by temperature crosstalk. SMS structure is not affected by solution concentration, but sensitive to ambient temperature. It can be used as a temperature compensation system. The sensitivity coefficients of LPFG and SMS on temperature and concentration were measured experimentally, and a dual-wavelength matrix was established to realize simultaneous measurement of solution temperature and concentration. </div>
基金973 Program(2014CB340003)National Natural Science Foundation of China(NSFC)(61307081,61321004,61420106003)
文摘We present a polarization-maintaining PANDA ring-core fiber(PM-PRCF) characterized by the combination of a ring-core structure with two stress-applying rods. This special fiber design separates the adjacent modes and avoids the cutoff of the higher-order modes, which is a common problem in elliptical core polarization-maintaining few-mode fibers. Using a high-contrast index ring and stress-induced birefringence, the PM-PRCF features support for 10 vector modes, with effective refractive index separations from their adjacent modes >10^(-4).Broadband performance is investigated subsequently over a wide wavelength range from 1500 to 1630 nm.The proposed fiber is targeted at applications in space-division multiplexing while eliminating the complex multiple-input multiple-output signal processing.
文摘Guided modes in a hollow optical fiber are investigated using both scalar approximation and exact vectorial analysis. Effective indices of modes are seen to exhibit "nearly degenerate" groups. Besides providing an insight of modal characteristics, the analysis would prove to be useful to define design parameters for realizing components based on these fibers, and to explore new possibilities.
基金supported in part by the National 973Program(No.2014CB340003)the National Nature Science Foundation of China(Nos.61307081,61621064,and 61420106003)the Chuangxin Funding
文摘We present the investigation on deformation of orbital angular momentum(OAM)modes in bending ring-core fibers(RCFs)with different structure sizes through numerical and experimental studies.The effective refractive index differences of even and odd fiber eigenmodes,which constitute OAM_(±1;1) modes,induced by RCF bending and their impacts on the OAM_(±1;1) mode intensity distributions are analyzed.Bending experiments are also carried out on three different RCFs,and the results match well with simulation values.It is found that RCFs with smaller inner and outer radii show preferable tolerance to the fiber bending.
基金supported by the National Natural Science Foundation of China(Grant Nos.62005011,61801017,and.62005013)the Beijing Municipal Natural Science Foundation(Grant No.4212009)the Fundamental Research Funds for the Central Universities(Grant No.2020RC015).
文摘An in-fiber Mach-Zehnder interferometer is proposed for the discrimination of strain and temperature.The sensor is based on two cascaded standard single mode fibers using three peanut tapers fabricated by simple splicing.The cascaded structure excites more frequency components,which induce four sets of interference dips in the transmission spectrum.One set of the spectrum dips have different sensitivities to temperature and strain from those of the other three.The sensor can discriminate strain and temperature by monitoring the wavelength shifts of two spectrum dips.Repeated experiments are taken both for strain and temperature increasing and decreasing scenarios.Experimental results show that Dip 1 has an average strain sensitivity of-0.911 pm/με and an average temperature sensitivity of 49.98pm/℃.The strain sensitivity for Dip 2 is negligible and its average temperature sensitivity is 60.52pm/℃.The strain and temperature resolutions are±3.82με and±0.33℃.
基金National Natural Science Foundation of China(NSFC)(61331010,61205063)863 High Technology plan(2015AA016904)Program for New Century Excellent Talents in University(NCET)(NCET-13-0235)
文摘We propose a novel waveguide design of polarization-maintaining few mode fiber(PM-FMF) supporting ≥10non-degenerate modes, utilizing a central circular air hole and a circumjacent elliptical-ring core. The structure endows a new degree of freedom to adjust the birefringence of all the guided modes, including the fundamental polarization mode. Numerical simulations demonstrate that, by optimizing the air hole and elliptical-ring core,a PM-FMF supporting 10 distinctive polarization modes has been achieved, and the effective index difference Δn_(eff) between the adjacent guided modes could be kept larger than 1.32 × 10^(-4) over the whole C +L band. The proposed fiber structure can flexibly tailored to support an even larger number of modes in PM-FMF(14-mode PM-FMF has been demonstrated as an example), which can be readily applicable to a scalable mode division multiplexing system.
基金This work was funded by the National Natural Science Foundation of China(NSFC)(Grant Nos.41266001,61665007,and 61865013)National Key Research and Development Project from the Ministry of Science and Technology(Grant No.2018YFE0115700)+1 种基金Science and Technology Project of Jiangxi Education Department(Grant No.GJJ180518)Nanchang Hangkong University graduate student innovation special fund project(Grant No.YC2019053).
文摘A Mach-Zehnder interferometer(MZI)for high temperature(1000°C)sensing based on few mode fiber(FMF)was proposed and experimentally demonstrated.The sensor was fabricated by fusing a section of FMF between two single-mode fibers(SMFs).The structure was proven to be an excellent high temperature sensor with good stability,repeatability,and high temperature sensitivity(48.2 pm/C)after annealing process at a high temperature lasting some hours,and a wide working temperature range(from room temperature to 1000 C).In addition,the simple fabrication process and the low cost offered a great potential for sensing in high temperature environments.
基金supported by the Fundamental Research Funds for the Central Universities (Grant Nos. 3102014JCQ01101, 3102014JCQ01099, and 3102014JCQ01085)the 973 Program (Grant No. 2012CB921900)the National Natural Science Foundation of China (Grant Nos. 61405161, 11404263, and 61377035)
文摘We propose a low-threshold soliton fiber laser passively mode locked with two different types of film-like saturable absorbers, one of which is fabricated by mixing Bi2Te3 with de-ionized water, as well as polyvinyl alcohol(PVA), and then evaporating them in a Petri dish, and the other of which is prepared by directly dropping Bi2Te3 solution on the PVA film. Both Bi2Te3–PVA films exhibit outstanding features of low loss, high flexibility, and easy synthesis. By incorporating Bi2Te3–PVA films into fiber lasers, stable single-soliton emissions are obtained at a low pump power of 13 mW. Our results suggest that the Bi2Te3 can work as a promising mode locker for ultrafast lasers,while PVA is an excellent host for fabricating high-performance film-based saturable absorbers.
基金supported by the National Natural Science Foundation of China(Nos.61475133 and 61575170)the Key Basic Research Program of Hebei Province(Nos.16961701D and QN2016078)+1 种基金the Natural Science Foundation of Hebei Province(Nos.F2015203270 and F2016203392)the“Xin Rui Gong Cheng”Talent Project of Yanshan University
文摘A refractive index insensitive temperature sensor based on waist-enlarged few mode fiber(FMF) bitapers is presented. The first section of FMF is spliced between two single-mode fibers. In fusion process,the waist-enlarged FMF bitapers can be obtained by large current discharging repeatedly. The refractive index and temperature sensing mechanisms are analyzed. For the sensors with different sizes,the refractive index and temperature experiments have been performed. The results show that in the refractive index ranges of 1.335 0—1.346 6 and 1.348 2—1.419 3,the refractive index insensitivity is verified. In a temperature range of 31.9—90 °C,the sensor sensitivity can be up to 85.57 pm/°C. In addition,it has a compact structure. Therefore,the sensor can avoid the cross sensitivity for measuring the refractive index and temperature simultaneously.
基金National Basic Research Program of China(2014CB340102)National Natural Science Foundation of China(NSFC)(61427813,61531003,61690195)
文摘Transverse mode characteristics of a laser are related to a variety of interesting applications. An on-demand mode solid laser in the 1064 nm band was proposed previously. In this paper, we provide a fiber laser for on-demand modes in the 1550 nm band to prescribe the pure and high-quality emission of a higher-order transverse laser mode, based on a simple construction with one spatial light modulator(SLM) and a single-mode erbium-doped fiber(SM-EDF). The SLM is designated to generate the desired higher-order mode and separate the higher-order mode and the fundamental mode. The fundamental mode oscillates in the fiber ring laser, and therefore the SM-EDF can be pumped with a single-mode 980 nm laser, no matter what higher-order mode is prescribed.In this proof-of-principle experiment, high-quality higher-order modes are observed from LP01 to LP105.Stable emission and real-time switching between modes can be easily realized by altering the phase on the SLM. In addition, the propagation of the LP_(01), LP_(11), LP_(21), and LP_(02) modes from the fiber laser is also demonstrated in a four-mode few-mode fiber.
基金supported in part by the National Natural Science Foundation of China under Grants 61575040 and 61106045the PCSIRT under Grant IRT1218+1 种基金the 111 Project under Grant B14039the open research fund of Jiangsu Key Laboratory for Advanced Optical Manufacturing Technologies under Grant KJS1402
文摘In this paper, we proposed a way to realize an Er-doped random fiber laser(RFL) with a disordered fiber Bragg grating(FBG) array, as well as to control the lasing mode of the RFL by heating specific locations of the disordered FBG array. The disordered FBG array performs as both the gain medium and random distributed reflectors, which together with a tunable point reflector form the RFL. Coherent multi-mode random lasing is obtained with a threshold of between 7.5 and 10 mW and a power efficiency between 23% and 27% when the reflectivity of the point reflector changes from 4% to 50%. To control the lasing mode of random emission, a specific point of the disordered FBG array is heated so as to shift the wavelength of the FBG(s) at this point away from the other FBGs.Thus, different resonance cavities are formed, and the lasing mode can be controlled by changing the location of the heating point.
基金the National Basic Research Program of China (973 Program) under Grant 2014CB340102the National Natural Science Foundation under Grants 61271191 and 61271193the Fund of State Key Laboratory of Information Photonics and Optical Communications
文摘In this paper, we present a mode-selective coupler based on a dual-core all-solid photonic bandgap fiber(AS-PBGF). Because they are all-solid, AS-PBGF-based mode converters are easier to splice to other fibers than those based on air-hole photonic crystal fibers. Mode conversions between the LP01 and LP11modes, LP01 and LP21modes, and LP01 and LP02modes are obtained at the wavelength λ=1550 nm. The 3 dB wavelength bandwidth of these mode converters are 47.8,20.3, and 20.3 nm, respectively.
文摘Core mode cutoff is a useful concept not only for a tapered single-core fiber(SCF) but also for a tapered multicore fiber(MCF) to realize cladding mode transmission. In this paper, cut-off conditions of either core mode for tapered SCFs or supermodes for MCFs are theoretically investigated. Rigorous analytical formulas are derived for the modes of SCF by a three-layer waveguide model, and an approximation formula of the cut-off condition is given for the LP01 mode. The supermodes of MCFs are analyzed by the coupling mode theory, and the cut-off condition is calculated by a numerical method. Simulation results show that the in-phase supermode of MCFs has a similar cut-off condition with that of SCF. Based on this property, a convenient approximate formula is given to estimate the cut-off condition of the in-phase supermode for tapered MCFs.
文摘Dispersion compensation with few-mode fibers is emerging as a promising technique that can provide full dispersion and dispersion-slope compensation. The inherent modal path diversity of these fibers allows implementation of static as well as tunable dispersion management schemes. In addition, the low non-linearity of this technology can improve system OSNR, leading to enhancements in transmission distances.
文摘A frequency domain analysis is presented to determine the performance characteristics of a tunable all-optical wavelength converter using four-wave mixing (FWM) in a single mode fiber (SMF) around the zero dispersion wavelength using two pump lasers. The output converted signal power as well as efficiency evaluated at a bit rate of 10 Gb/s show that the signal power is substantially higher at lower values of wavelength separation.
文摘Transmission of 40Gbit/s NRZ signal was successfully demonstrated over 219km of installed SMF in KT's Daejeon area network. After transmission, the measured power penalty was 0.5dB for all the tributary channels.
文摘We measured macro-bending losses for two large mode area photonic crystal fibers. Experimental results show that macro-bending loss and loss window are dependent on the parameter d/∧ and number of air-holes ring in the cladding.