We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber ...We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber (EDF) to form an asymmetric three-cavity structure. The stable SLM operation at a wavelength of 1545.112 nm with a 3-dB bandwidth of 0.012 nm and an optical signal-to-noise ratio (OSNR) of about 60 dB is verified experimentally. Under laboratory conditions, the performance of a power fluctuation of less than 0.05 dB observed from the power meter for 6 h and a wavelength variation of less than 0.01 nm obtained from the optical spectrum analyzer (OSA) for about 1.5 h are demonstrated. The gain fiber length is no longer limited to only several centimeters for SLM operation because of the excellent mode-selecting ability of the asymmetric three-cavity structure. The proposed scheme provides a simple and cost-effective approach to realizing a stable SLM fiber laser.展开更多
In this paper,the chaotic behaviors in an erbium-doped fiber(EDF) single-ring laser(EDFSRL) are investigated experimentally by using the loss modulation method.An electro-optic modulator(EOM) made of LiNbO 3 cry...In this paper,the chaotic behaviors in an erbium-doped fiber(EDF) single-ring laser(EDFSRL) are investigated experimentally by using the loss modulation method.An electro-optic modulator(EOM) made of LiNbO 3 crystal is added to the system.Thus,by changing the modulation voltage and the modulation frequency of the EOM,the freedom of the EDFSRL system is increased.The chaotic characteristics of the system are studied by observing the time series and the power spectra.The experimental results indicate that the erbium-doped fiber single-ring laser system can enter into chaos states through period-doubling bifurcation and intermittency routes.展开更多
The configuration of the novel three-stage L-band erbium-doped fiber amplifier with very large and flat gain and very low noise figure presented in this paper uses the forward ASE (amplified spontaneous emission) from...The configuration of the novel three-stage L-band erbium-doped fiber amplifier with very large and flat gain and very low noise figure presented in this paper uses the forward ASE (amplified spontaneous emission) from the first section of the EDF (erbium-doped fiber) and the backward ASE from the third section of the EDF (both serve as the secondary pump sources of energy) to pump the second EDF. To improve the pump efficiency, the power of the pump is split into two parts (with a ratio of e.g. 2:7). The characteristics of this L-band EDFA are studied on the basis of the Giles Model with ASE.展开更多
Bidirectional EDFAs(Bi-EDFAs)featuring bidirectional signal input are theoreticallystudied.Gain and noise performances of Bi-EDFAs are analysed numerically and comparedwith that of other optical amplifiers.Application...Bidirectional EDFAs(Bi-EDFAs)featuring bidirectional signal input are theoreticallystudied.Gain and noise performances of Bi-EDFAs are analysed numerically and comparedwith that of other optical amplifiers.Applications of Bi-EDFAs in fiber networks and otherfields are considered.展开更多
An all fiber wavelength selective Q switching modulator based on fiber grating loop mirror is proposed. A newly configured Q switched erbium doped fiber laser using this all fiber modulator is numerically analyzed tak...An all fiber wavelength selective Q switching modulator based on fiber grating loop mirror is proposed. A newly configured Q switched erbium doped fiber laser using this all fiber modulator is numerically analyzed taking into account the effects of the spontaneous emission.展开更多
In this paper, new configuration is proposed, investigated and analyzed. Fiber laser and fiber amplifier are merged in one configuration which called Erbium Doped Fiber Laser and Amplifier (EDFLA) or integrating EDFL ...In this paper, new configuration is proposed, investigated and analyzed. Fiber laser and fiber amplifier are merged in one configuration which called Erbium Doped Fiber Laser and Amplifier (EDFLA) or integrating EDFL and EDFA in one design. The configuration has three main outputs;one for laser, second for amplifier and the third it can be used for on/off output. A surprising phenomenon was remarked during the operation of this configuration. The amplification is abolished during the lasing state and appeared again if the lasing is stopped or the switch is off. The difference between outputs with the lasing and without lasing has 30 dB EDFA gain value;it is a good sign that this optical configuration can be used as an on/off integrated optical device for fiber laser.展开更多
<span style="font-family:Verdana;">T</span><span style="font-family:Verdana;font-size:12px;">he T</span><span style="font-family:Verdana;font-size:12px;">i&l...<span style="font-family:Verdana;">T</span><span style="font-family:Verdana;font-size:12px;">he T</span><span style="font-family:Verdana;font-size:12px;">i</span><span style="font-family:Verdana;font-size:12px;">Se</span><sub><span style="font-family:Verdana;font-size:12px;">2</span></sub><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">nanosheets</span><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">were</span><span style="font-family:Verdana;font-size:12px;"> prepared by means of ultrasound-assisted liquid </span><span style="font-family:Verdana;font-size:12px;">phase exfoliation (LPE)</span><span style="font-family:Verdana;font-size:12px;"> and the </span><span style="font-family:Verdana;font-size:12px;">nonlinear </span><span style="font-family:Verdana;font-size:12px;">saturable absorption</span><span style="font-family:Verdana;font-size:12px;"> properties</span><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">were experimentally</span><span style="font-family:Verdana;font-size:12px;"> investigated. The modulation depth, saturation intensity and nonsaturable absorbance</span><span style="font-family:Verdana;font-size:12px;"> of the prepared </span><span style="font-family:Verdana;font-size:12px;">1T-TiSe</span><sub><span style="font-family:Verdana;font-size:12px;">2</span></sub><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">SA </span><span style="font-family:Verdana;font-size:12px;">were</span><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">1</span><span style="font-family:Verdana;font-size:12px;">5.7</span><span style="font-family:Verdana;font-size:12px;">%,</span><span style="font-family:Verdana;font-size:12px;"> 1.28 M</span><span style="font-family:Verdana;font-size:12px;">W/cm</span><sup><span style="font-family:Verdana;font-size:12px;vertical-align:super;">2</span></sup><span style="font-family:Verdana;font-size:12px;"> and 8.</span><span style="font-family:Verdana;font-size:12px;">2</span><span style="font-family:Verdana;font-size:12px;">%, </span><span style="font-family:Verdana;font-size:12px;">respectively</span><span style="font-family:Verdana;font-size:12px;">. Taking advantage of the saturable absorption properties of </span><span style="font-family:Verdana;font-size:12px;">T</span><span style="font-family:Verdana;font-size:12px;">i</span><span style="font-family:Verdana;font-size:12px;">Se</span><sub><span style="font-family:Verdana;font-size:12px;">2</span></sub><span style="font-family:Verdana;font-size:12px;">-based SA, a passively Q-switched erbium-doped fiber (EDF) laser was</span><span style="font-family:Verdana;font-size:12px;"> systematically demonstrated</span><span style="font-family:Verdana;font-size:12px;">. The pulse repetition rates varied from 24.50 kHz up to 73.79 kHz with the increasing pump power. The obtained shortest pulse width was 1.31 </span><span style="font-family:Verdana;font-size:12px;">μ</span><span style="font-family:Verdana;font-size:12px;">s with pulse energy of 79.28 nJ. The </span><span style="font-family:Verdana;font-size:12px;">system presented merits of low-cost SA preparation, system compactness,</span><span style="font-family:Verdana;font-size:12px;"> superb stability and high competition.</span>展开更多
It is crucial to study the effect of radiation on the fiber amplifier devices. In the present paper, the Erbium-ytterbium co-doped fiber amplifier (EYDFA) has been irradiated by a neutron beam of different doses for v...It is crucial to study the effect of radiation on the fiber amplifier devices. In the present paper, the Erbium-ytterbium co-doped fiber amplifier (EYDFA) has been irradiated by a neutron beam of different doses for various exposure times from an Am-241/Be-9 neutron source. The gain and noise figure of the EYDFA have been calculated theoretically and recorded after and before the irradiation to test its performance under the effect of irradiation. In order to show the enhancement in the gain of the fiber amplifier devices, a comparison between the gain of the irradiated EYDFA and Erbium doped Fiber amplifier (EDFA) has been carried out. The calculated results by the proposed model are in good agreement with the experimental ones. It indicates that the gain of EYDFA deteriorates after being irradiated by a neutron dose. Moreover, the gain of irradiated EYDFA has been reduced to 13.8 dB at a dose of 720 Gy.展开更多
GeSe nanosheets were prepared by ultrasonic-assisted liquid<span><span><span style="font-family:;" "=""> </span></span></span><span><span><sp...GeSe nanosheets were prepared by ultrasonic-assisted liquid<span><span><span style="font-family:;" "=""> </span></span></span><span><span><span><span style="font-family:Verdana;">phase exfoliation (LPE), and the nonlinear saturated absorption performance was experimentally studied. The modulation depth and saturation intensity of the prepared GeSe saturable absorber (SA) were 15% and 1.44 MW/cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, respectively. Us</span><span style="font-family:Verdana;">ing the saturated absorption characteristics of GeSe SA, a passively Q-switched </span><span style="font-family:Verdana;">erbium-doped fiber laser was systematically demonstrated. As the pump</span><span style="font-family:Verdana;"> power increases, the pulse repetition frequency increases from 22.8 kHz to 77.59 </span><span style="font-family:Verdana;">kHz. The shortest pulse duration is 1.51 μs, and the corresponding pulse</span><span style="font-family:Verdana;"> energy is 46.14 nJ. Experimental results show that GeSe nanosheets can be used as high-efficiency SA in fiber lasers. Our results will provide a useful reference for demonstrating pulsed fiber lasers based on GeSe equipment.</span></span></span></span>展开更多
The rate equation model is setup for the signal gain, pump absorption and output noise spectrum of bidirectional EDFA (Bi EDFA) including numbers of signals, pumps of arbitrary direction, amplified spontaneous emissi...The rate equation model is setup for the signal gain, pump absorption and output noise spectrum of bidirectional EDFA (Bi EDFA) including numbers of signals, pumps of arbitrary direction, amplified spontaneous emission (ASE) and inherent loss. The influence of erbium doped fiber length, input signal power, pump style and pump power on the gain characteristics of Bi EDFA is analyzed. Forward and backward noise figure for different pump style versus bidirectional input signal power is investigated.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61077069 and 61107094)the Innovation Foundation for Excellent Doctoral Candidates of Beijing Jiaotong University, China (Grant No. 2011YJS202)
文摘We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber (EDF) to form an asymmetric three-cavity structure. The stable SLM operation at a wavelength of 1545.112 nm with a 3-dB bandwidth of 0.012 nm and an optical signal-to-noise ratio (OSNR) of about 60 dB is verified experimentally. Under laboratory conditions, the performance of a power fluctuation of less than 0.05 dB observed from the power meter for 6 h and a wavelength variation of less than 0.01 nm obtained from the optical spectrum analyzer (OSA) for about 1.5 h are demonstrated. The gain fiber length is no longer limited to only several centimeters for SLM operation because of the excellent mode-selecting ability of the asymmetric three-cavity structure. The proposed scheme provides a simple and cost-effective approach to realizing a stable SLM fiber laser.
基金Project supported by the Science and Technology Development Program of Jilin Province,China (Grant No. 20090309)
文摘In this paper,the chaotic behaviors in an erbium-doped fiber(EDF) single-ring laser(EDFSRL) are investigated experimentally by using the loss modulation method.An electro-optic modulator(EOM) made of LiNbO 3 crystal is added to the system.Thus,by changing the modulation voltage and the modulation frequency of the EOM,the freedom of the EDFSRL system is increased.The chaotic characteristics of the system are studied by observing the time series and the power spectra.The experimental results indicate that the erbium-doped fiber single-ring laser system can enter into chaos states through period-doubling bifurcation and intermittency routes.
文摘The configuration of the novel three-stage L-band erbium-doped fiber amplifier with very large and flat gain and very low noise figure presented in this paper uses the forward ASE (amplified spontaneous emission) from the first section of the EDF (erbium-doped fiber) and the backward ASE from the third section of the EDF (both serve as the secondary pump sources of energy) to pump the second EDF. To improve the pump efficiency, the power of the pump is split into two parts (with a ratio of e.g. 2:7). The characteristics of this L-band EDFA are studied on the basis of the Giles Model with ASE.
基金a major project of the 8th Five-Year Plan of China.
文摘Bidirectional EDFAs(Bi-EDFAs)featuring bidirectional signal input are theoreticallystudied.Gain and noise performances of Bi-EDFAs are analysed numerically and comparedwith that of other optical amplifiers.Applications of Bi-EDFAs in fiber networks and otherfields are considered.
文摘An all fiber wavelength selective Q switching modulator based on fiber grating loop mirror is proposed. A newly configured Q switched erbium doped fiber laser using this all fiber modulator is numerically analyzed taking into account the effects of the spontaneous emission.
文摘In this paper, new configuration is proposed, investigated and analyzed. Fiber laser and fiber amplifier are merged in one configuration which called Erbium Doped Fiber Laser and Amplifier (EDFLA) or integrating EDFL and EDFA in one design. The configuration has three main outputs;one for laser, second for amplifier and the third it can be used for on/off output. A surprising phenomenon was remarked during the operation of this configuration. The amplification is abolished during the lasing state and appeared again if the lasing is stopped or the switch is off. The difference between outputs with the lasing and without lasing has 30 dB EDFA gain value;it is a good sign that this optical configuration can be used as an on/off integrated optical device for fiber laser.
文摘<span style="font-family:Verdana;">T</span><span style="font-family:Verdana;font-size:12px;">he T</span><span style="font-family:Verdana;font-size:12px;">i</span><span style="font-family:Verdana;font-size:12px;">Se</span><sub><span style="font-family:Verdana;font-size:12px;">2</span></sub><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">nanosheets</span><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">were</span><span style="font-family:Verdana;font-size:12px;"> prepared by means of ultrasound-assisted liquid </span><span style="font-family:Verdana;font-size:12px;">phase exfoliation (LPE)</span><span style="font-family:Verdana;font-size:12px;"> and the </span><span style="font-family:Verdana;font-size:12px;">nonlinear </span><span style="font-family:Verdana;font-size:12px;">saturable absorption</span><span style="font-family:Verdana;font-size:12px;"> properties</span><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">were experimentally</span><span style="font-family:Verdana;font-size:12px;"> investigated. The modulation depth, saturation intensity and nonsaturable absorbance</span><span style="font-family:Verdana;font-size:12px;"> of the prepared </span><span style="font-family:Verdana;font-size:12px;">1T-TiSe</span><sub><span style="font-family:Verdana;font-size:12px;">2</span></sub><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">SA </span><span style="font-family:Verdana;font-size:12px;">were</span><span style="font-family:Verdana;font-size:12px;"> </span><span style="font-family:Verdana;font-size:12px;">1</span><span style="font-family:Verdana;font-size:12px;">5.7</span><span style="font-family:Verdana;font-size:12px;">%,</span><span style="font-family:Verdana;font-size:12px;"> 1.28 M</span><span style="font-family:Verdana;font-size:12px;">W/cm</span><sup><span style="font-family:Verdana;font-size:12px;vertical-align:super;">2</span></sup><span style="font-family:Verdana;font-size:12px;"> and 8.</span><span style="font-family:Verdana;font-size:12px;">2</span><span style="font-family:Verdana;font-size:12px;">%, </span><span style="font-family:Verdana;font-size:12px;">respectively</span><span style="font-family:Verdana;font-size:12px;">. Taking advantage of the saturable absorption properties of </span><span style="font-family:Verdana;font-size:12px;">T</span><span style="font-family:Verdana;font-size:12px;">i</span><span style="font-family:Verdana;font-size:12px;">Se</span><sub><span style="font-family:Verdana;font-size:12px;">2</span></sub><span style="font-family:Verdana;font-size:12px;">-based SA, a passively Q-switched erbium-doped fiber (EDF) laser was</span><span style="font-family:Verdana;font-size:12px;"> systematically demonstrated</span><span style="font-family:Verdana;font-size:12px;">. The pulse repetition rates varied from 24.50 kHz up to 73.79 kHz with the increasing pump power. The obtained shortest pulse width was 1.31 </span><span style="font-family:Verdana;font-size:12px;">μ</span><span style="font-family:Verdana;font-size:12px;">s with pulse energy of 79.28 nJ. The </span><span style="font-family:Verdana;font-size:12px;">system presented merits of low-cost SA preparation, system compactness,</span><span style="font-family:Verdana;font-size:12px;"> superb stability and high competition.</span>
文摘It is crucial to study the effect of radiation on the fiber amplifier devices. In the present paper, the Erbium-ytterbium co-doped fiber amplifier (EYDFA) has been irradiated by a neutron beam of different doses for various exposure times from an Am-241/Be-9 neutron source. The gain and noise figure of the EYDFA have been calculated theoretically and recorded after and before the irradiation to test its performance under the effect of irradiation. In order to show the enhancement in the gain of the fiber amplifier devices, a comparison between the gain of the irradiated EYDFA and Erbium doped Fiber amplifier (EDFA) has been carried out. The calculated results by the proposed model are in good agreement with the experimental ones. It indicates that the gain of EYDFA deteriorates after being irradiated by a neutron dose. Moreover, the gain of irradiated EYDFA has been reduced to 13.8 dB at a dose of 720 Gy.
文摘GeSe nanosheets were prepared by ultrasonic-assisted liquid<span><span><span style="font-family:;" "=""> </span></span></span><span><span><span><span style="font-family:Verdana;">phase exfoliation (LPE), and the nonlinear saturated absorption performance was experimentally studied. The modulation depth and saturation intensity of the prepared GeSe saturable absorber (SA) were 15% and 1.44 MW/cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, respectively. Us</span><span style="font-family:Verdana;">ing the saturated absorption characteristics of GeSe SA, a passively Q-switched </span><span style="font-family:Verdana;">erbium-doped fiber laser was systematically demonstrated. As the pump</span><span style="font-family:Verdana;"> power increases, the pulse repetition frequency increases from 22.8 kHz to 77.59 </span><span style="font-family:Verdana;">kHz. The shortest pulse duration is 1.51 μs, and the corresponding pulse</span><span style="font-family:Verdana;"> energy is 46.14 nJ. Experimental results show that GeSe nanosheets can be used as high-efficiency SA in fiber lasers. Our results will provide a useful reference for demonstrating pulsed fiber lasers based on GeSe equipment.</span></span></span></span>
文摘The rate equation model is setup for the signal gain, pump absorption and output noise spectrum of bidirectional EDFA (Bi EDFA) including numbers of signals, pumps of arbitrary direction, amplified spontaneous emission (ASE) and inherent loss. The influence of erbium doped fiber length, input signal power, pump style and pump power on the gain characteristics of Bi EDFA is analyzed. Forward and backward noise figure for different pump style versus bidirectional input signal power is investigated.