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
Presented is a theoretical study of double-clad Er-doped fiber power amplifier(EDFA). Two kinds of double clad fibers(DCF) with rectangular and "flower" inner clad shapes are studied, and these fibers have d...Presented is a theoretical study of double-clad Er-doped fiber power amplifier(EDFA). Two kinds of double clad fibers(DCF) with rectangular and "flower" inner clad shapes are studied, and these fibers have different coupling constants and propagation losses. We calculate the effective pump power absorption ratio along the fiber with different coupling constants from the first cladding to the doped core and with different propagation losses for the power in the inner cladding. Then the gains of the double clad Er-doped fiber amplifiers versus fiber lengths are calculated using the EDFA model based on propagation and rate equations of a homogeneous, two-level medium.展开更多
To obtain a stable amplified spontaneous emission（ASE） source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperature...To obtain a stable amplified spontaneous emission（ASE） source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperatures.We optimize the structure of the ASE source to flatten the ASE spectrum, and study the output characteristics in terms of output power and optical spectrum under different pump powers. Then the performance of the ASE source is investigated in the temperature range from-18.9°C to 50°C. A stable-power and flat-spectrum ASE source can be obtained by structural optimization and pump control.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
We report here a high-power, wavelength tunable and narrow linewidth 1.5 μm all-fiber laser amplifier based on a tunable diode laser and Er-Yb co-doped fibers. The laser wavelength can be precisely tuned from 1535 nm...We report here a high-power, wavelength tunable and narrow linewidth 1.5 μm all-fiber laser amplifier based on a tunable diode laser and Er-Yb co-doped fibers. The laser wavelength can be precisely tuned from 1535 nm to 1580 nm, which covers many absorption lines of mid-infrared laser gases, such as C2 H2, HCN, CO, and HI. The maximum laser power is >11 W, and the linewidth is about 200–300 MHz, which is close to the absorption linewidth of the above-mentioned gases. This work provides a suitable pump source for high-power wavelength tunable mid-infrared fiber gas lasers based on low-loss hollow-core fibers.展开更多
An all-optical wavelength reuse technique employing cost effective power efficient vertical surface emitting laser(VCSEL) is proposed to address uplink data streaming from end-users by exploiting the same wavelength a...An all-optical wavelength reuse technique employing cost effective power efficient vertical surface emitting laser(VCSEL) is proposed to address uplink data streaming from end-users by exploiting the same wavelength assigned to them. A saturated optical erbium-doped optical fiber amplifier(EDFA) is adopted to erase a directly modulated 10 Gbit/s data from an incoming downstream wavelength. We show that with EDFA saturation, the extinction ration of the incoming wavelength is reduced to less than 1 d Bm, therefore allowing for wavelength re-modulation. A receiver sensitivity of -19.65 d Bm and -17.86 d Bm is attained for downstream and upstream data signals respectively. A total of 24.7 km single mode fibre transmission is attained experimentally. This technique opens new perspectives towards development of efficient spectrum utilization for application in wavelength flexible optical networks with non-static flex-spectrum grids.展开更多
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.
基金Foundation of Beijing Jiaotong University(2005RC034)
文摘Presented is a theoretical study of double-clad Er-doped fiber power amplifier(EDFA). Two kinds of double clad fibers(DCF) with rectangular and "flower" inner clad shapes are studied, and these fibers have different coupling constants and propagation losses. We calculate the effective pump power absorption ratio along the fiber with different coupling constants from the first cladding to the doped core and with different propagation losses for the power in the inner cladding. Then the gains of the double clad Er-doped fiber amplifiers versus fiber lengths are calculated using the EDFA model based on propagation and rate equations of a homogeneous, two-level medium.
基金Supported by the National Natural Science Foundation of China under Grant No 11504320
文摘To obtain a stable amplified spontaneous emission（ASE） source for complex environment applications, we design an ASE source and study the output power and spectral characteristics under different ambient temperatures.We optimize the structure of the ASE source to flatten the ASE spectrum, and study the output characteristics in terms of output power and optical spectrum under different pump powers. Then the performance of the ASE source is investigated in the temperature range from-18.9°C to 50°C. A stable-power and flat-spectrum ASE source can be obtained by structural optimization and pump control.
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.
基金supported by the National Natural Science Foundation of China(No.11274385)
文摘We report here a high-power, wavelength tunable and narrow linewidth 1.5 μm all-fiber laser amplifier based on a tunable diode laser and Er-Yb co-doped fibers. The laser wavelength can be precisely tuned from 1535 nm to 1580 nm, which covers many absorption lines of mid-infrared laser gases, such as C2 H2, HCN, CO, and HI. The maximum laser power is >11 W, and the linewidth is about 200–300 MHz, which is close to the absorption linewidth of the above-mentioned gases. This work provides a suitable pump source for high-power wavelength tunable mid-infrared fiber gas lasers based on low-loss hollow-core fibers.
文摘An all-optical wavelength reuse technique employing cost effective power efficient vertical surface emitting laser(VCSEL) is proposed to address uplink data streaming from end-users by exploiting the same wavelength assigned to them. A saturated optical erbium-doped optical fiber amplifier(EDFA) is adopted to erase a directly modulated 10 Gbit/s data from an incoming downstream wavelength. We show that with EDFA saturation, the extinction ration of the incoming wavelength is reduced to less than 1 d Bm, therefore allowing for wavelength re-modulation. A receiver sensitivity of -19.65 d Bm and -17.86 d Bm is attained for downstream and upstream data signals respectively. A total of 24.7 km single mode fibre transmission is attained experimentally. This technique opens new perspectives towards development of efficient spectrum utilization for application in wavelength flexible optical networks with non-static flex-spectrum grids.
