In this work the results of polarization researches of low-optical fiber waveguides with conservation of polarization are presented. Obtained results quite convincingly testify regarding a high sensitivity low-mode re...In this work the results of polarization researches of low-optical fiber waveguides with conservation of polarization are presented. Obtained results quite convincingly testify regarding a high sensitivity low-mode regime of work of an optical fiber to anisotropic external influences, in comparison with one-mode regime of work of the same fibre. This result, can represent a big practical value at the realization of high-sensitivity fiber-optical devices of different physical values.展开更多
This paper presents the design and analysis of optical filters that are placed at the output of directly modulated vertical cavity surface emitting laser (VCSEL) in the process of inexpensive transmitter's implemen...This paper presents the design and analysis of optical filters that are placed at the output of directly modulated vertical cavity surface emitting laser (VCSEL) in the process of inexpensive transmitter's implementation for upcoming generation optical access network. Generation of non return to zero (NRZ) optical signal from the transmitter for 110 km error-free single mode fiber (SMF) transmission at 10 Gb/s with bit error rate (BER) of 10-30 in the absence of the external modulator and encoder was proposed. Effects of super-Gaussian and Butterworth optical filters at VCSEL output were demonstrated to maximize performance of SMF optical systems without need of any dispersion compensation technique.展开更多
Stimulated Raman scattering (SRS) transmission modes in highly elliptical-core optical fiber of three different structures are experimentally researched.The measuring setup,SRS spectrum and photographs of Stokes modes...Stimulated Raman scattering (SRS) transmission modes in highly elliptical-core optical fiber of three different structures are experimentally researched.The measuring setup,SRS spectrum and photographs of Stokes modes are given.The observed phenomena are completely different from those on circular-core graded-index optical fiber.The beam sizes of SRS remain constant and SRS light transmits with the characteristics of higher-order.mode.In addition,the experimental results are theoretically explained with fiber-optical dispersion theory and SRS phase matching conditions.Experimental results and theoretical analyses are in good agreement.展开更多
The synthetic effects of group-velocity mismatch and cubic-quintic nonlinearity on cross-phase modulation induced modulation instability in loss single-mode optical fibers have been numerically investigated. The resul...The synthetic effects of group-velocity mismatch and cubic-quintic nonlinearity on cross-phase modulation induced modulation instability in loss single-mode optical fibers have been numerically investigated. The results show that the quintic nonlinearity plays a role similar to the case of neglecting the group-velocity mismatch in modifying the modulation instability, namely, the positive and negative quintic nonlinearities can still enhance and weaken the modulation instability, respectively. The group-velocity mismatch can considerably change the gain spectrum of modulation instability in terms of its shape, peak value, and position. In the normal dispersion regime, with the increase of the group-velocity mismatch parameter, the gain spectrum widens and then narrows, shifts to higher frequencies, and the peak value gets higher before approaching a saturable value. In the abnormal dispersion regime, two separated spectra may occur when the group-velocity mismatch is taken into account. With the increase of the group-velocity mismatch parameter, the peak value of the gain spectrum gets higher and shorter before tending to a saturable value for the first and second spectral regimes, respectively.展开更多
A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica fibers.After adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which ca...A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica fibers.After adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved ultimately.With the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000μm).This new generation of POFs will find many展开更多
In this paper the expression of the output pulse Stokes vector is derived based on the Jones matrix model proposed by A.Orlandini et al. The basic properties of degree of polarization (DOP) for output pulse are invest...In this paper the expression of the output pulse Stokes vector is derived based on the Jones matrix model proposed by A.Orlandini et al. The basic properties of degree of polarization (DOP) for output pulse are investigated.展开更多
The modulation phase shift method was used to measure chromatic dispersion in a standard single mode fiber for telecommunication. The modulation phase difference of the transmitted light at the wavelength of 1532.16 n...The modulation phase shift method was used to measure chromatic dispersion in a standard single mode fiber for telecommunication. The modulation phase difference of the transmitted light at the wavelength of 1532.16 nm modulated by a radio frequency signal was measured, relative to the transmitted light at the wavelength of 1549.33 nm modulated by the same signal. By introducing a reference light at the wavelength of 1310 nm, a 1310/1550 nm wavelength division multiplexing was used instead of the high cost dense wavelength division multiplexing. In the experiment, two testing lights were coupled with the reference light to the fiber spools of different lengths, respectively. By finite difference method, the chromatic dispersion between the two testing lights was measured, and the fixed errors generated during transmission were less than 0.5 ps/(nm·km).展开更多
Using differential detection, we perform polarization-multiplexing 160-Gb/s optical non-return-to-zero (NRZ) differential quadrature phase shift keying (DQPSK) signal transmission over 100-kin standard single mode...Using differential detection, we perform polarization-multiplexing 160-Gb/s optical non-return-to-zero (NRZ) differential quadrature phase shift keying (DQPSK) signal transmission over 100-kin standard single mode fiber at a bit error rate (BER) of less than 10^-9. The enabling technology includes clock recovery, fine dispersion compensation, and polarization tracking for de-multiplexing. Furthermore, a hybrid clock recovery scheme is proposed. The scheme is realized with ordinary devices using an optoelectrical modulator to down-convert the clock frequency and a phase-locked loop for filtering, which can provide an indication signal that simultaneously monitors residual dispersion and tracking polarization.展开更多
An experimental demonstration of an all-optical sampling orthogonal frequency division multiplexing (AOS-OFDM) transmission system with inline chromatic dispersion (CD) compensation is carried out to test the nonl...An experimental demonstration of an all-optical sampling orthogonal frequency division multiplexing (AOS-OFDM) transmission system with inline chromatic dispersion (CD) compensation is carried out to test the nonlinear influence. With five subcarriers non-return-to-zero (NRZ) modulated, the total bit rate is 50 Gb/s without polarization multiplexing. The receiver end is highly simplified with direct de- tection using optical Fourier transform filter. After transmission in 160-km standard single-mode fiber (SSMF) link with 130-ps/nm residual CD, an optimum input optical power for the system performance is achieved.展开更多
In this paper, the characteristics of soliton in a passively mode-locked Er-doped fiber laser modeled by a non-distributed model are numerically investigated with the split-step Fourier method. Based on the analysis a...In this paper, the characteristics of soliton in a passively mode-locked Er-doped fiber laser modeled by a non-distributed model are numerically investigated with the split-step Fourier method. Based on the analysis and model, sech2-shaped soliton is obtained by controlling the group velocity dispersion (GVD) and small-signal gain of the gain fiber. The law that the dispersion influences the characteristics of soliton in the mode-locked fiber laser is researched in net-cavity averaged anomalous dispersion regime.展开更多
文摘In this work the results of polarization researches of low-optical fiber waveguides with conservation of polarization are presented. Obtained results quite convincingly testify regarding a high sensitivity low-mode regime of work of an optical fiber to anisotropic external influences, in comparison with one-mode regime of work of the same fibre. This result, can represent a big practical value at the realization of high-sensitivity fiber-optical devices of different physical values.
文摘This paper presents the design and analysis of optical filters that are placed at the output of directly modulated vertical cavity surface emitting laser (VCSEL) in the process of inexpensive transmitter's implementation for upcoming generation optical access network. Generation of non return to zero (NRZ) optical signal from the transmitter for 110 km error-free single mode fiber (SMF) transmission at 10 Gb/s with bit error rate (BER) of 10-30 in the absence of the external modulator and encoder was proposed. Effects of super-Gaussian and Butterworth optical filters at VCSEL output were demonstrated to maximize performance of SMF optical systems without need of any dispersion compensation technique.
文摘Stimulated Raman scattering (SRS) transmission modes in highly elliptical-core optical fiber of three different structures are experimentally researched.The measuring setup,SRS spectrum and photographs of Stokes modes are given.The observed phenomena are completely different from those on circular-core graded-index optical fiber.The beam sizes of SRS remain constant and SRS light transmits with the characteristics of higher-order.mode.In addition,the experimental results are theoretically explained with fiber-optical dispersion theory and SRS phase matching conditions.Experimental results and theoretical analyses are in good agreement.
基金the Fundamental Application Research Project Supported by the Science and Technology Department of Sichuan Province(No.05JY029-084,04JY029-103)the Major Project of Natural Science Supported by the Education Department of Sichuan Province(No.2006A124)and the Science and Technology Development Foundation of Chengdu University of Information Technology(No.KYTZ20060604).
文摘The synthetic effects of group-velocity mismatch and cubic-quintic nonlinearity on cross-phase modulation induced modulation instability in loss single-mode optical fibers have been numerically investigated. The results show that the quintic nonlinearity plays a role similar to the case of neglecting the group-velocity mismatch in modifying the modulation instability, namely, the positive and negative quintic nonlinearities can still enhance and weaken the modulation instability, respectively. The group-velocity mismatch can considerably change the gain spectrum of modulation instability in terms of its shape, peak value, and position. In the normal dispersion regime, with the increase of the group-velocity mismatch parameter, the gain spectrum widens and then narrows, shifts to higher frequencies, and the peak value gets higher before approaching a saturable value. In the abnormal dispersion regime, two separated spectra may occur when the group-velocity mismatch is taken into account. With the increase of the group-velocity mismatch parameter, the peak value of the gain spectrum gets higher and shorter before tending to a saturable value for the first and second spectral regimes, respectively.
基金the National Natural Science Foundation of China(Grant Nos.60444003,60577009)
文摘A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica fibers.After adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved ultimately.With the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000μm).This new generation of POFs will find many
文摘In this paper the expression of the output pulse Stokes vector is derived based on the Jones matrix model proposed by A.Orlandini et al. The basic properties of degree of polarization (DOP) for output pulse are investigated.
基金Doctoral Foundation of Education Ministry of China(No 20040056008) National Natural Science Foundation ofChina (No 50539060)
文摘The modulation phase shift method was used to measure chromatic dispersion in a standard single mode fiber for telecommunication. The modulation phase difference of the transmitted light at the wavelength of 1532.16 nm modulated by a radio frequency signal was measured, relative to the transmitted light at the wavelength of 1549.33 nm modulated by the same signal. By introducing a reference light at the wavelength of 1310 nm, a 1310/1550 nm wavelength division multiplexing was used instead of the high cost dense wavelength division multiplexing. In the experiment, two testing lights were coupled with the reference light to the fiber spools of different lengths, respectively. By finite difference method, the chromatic dispersion between the two testing lights was measured, and the fixed errors generated during transmission were less than 0.5 ps/(nm·km).
基金supported in part by the National Natural Science Foundation of China(Nos. 60736003,61025004,and 61032005)the National "863" Program of China(Nos.2009AA01Z223 and 2009AA01Z253)
文摘Using differential detection, we perform polarization-multiplexing 160-Gb/s optical non-return-to-zero (NRZ) differential quadrature phase shift keying (DQPSK) signal transmission over 100-kin standard single mode fiber at a bit error rate (BER) of less than 10^-9. The enabling technology includes clock recovery, fine dispersion compensation, and polarization tracking for de-multiplexing. Furthermore, a hybrid clock recovery scheme is proposed. The scheme is realized with ordinary devices using an optoelectrical modulator to down-convert the clock frequency and a phase-locked loop for filtering, which can provide an indication signal that simultaneously monitors residual dispersion and tracking polarization.
基金supported by the National Natural Science Foundation of China (Nos. 60736002, 60807026,60932004, and 61090391)the Open Fund of Key Laboratory of Optical Communication and Lightwave Technologies (BUPT), Ministry of Education, Chinathe State Key Laboratory of Advanced Optical Communication Systems and Networks, China (No. 2008SH03)
文摘An experimental demonstration of an all-optical sampling orthogonal frequency division multiplexing (AOS-OFDM) transmission system with inline chromatic dispersion (CD) compensation is carried out to test the nonlinear influence. With five subcarriers non-return-to-zero (NRZ) modulated, the total bit rate is 50 Gb/s without polarization multiplexing. The receiver end is highly simplified with direct de- tection using optical Fourier transform filter. After transmission in 160-km standard single-mode fiber (SSMF) link with 130-ps/nm residual CD, an optimum input optical power for the system performance is achieved.
基金supported by the Natural Science Foundation of Jilin (201115027)the National Natural Science Foundation of China (61171079)
文摘In this paper, the characteristics of soliton in a passively mode-locked Er-doped fiber laser modeled by a non-distributed model are numerically investigated with the split-step Fourier method. Based on the analysis and model, sech2-shaped soliton is obtained by controlling the group velocity dispersion (GVD) and small-signal gain of the gain fiber. The law that the dispersion influences the characteristics of soliton in the mode-locked fiber laser is researched in net-cavity averaged anomalous dispersion regime.