Erbium doped borate glass is widely used in luminescent materials,the luminescence dynamics of erbium doped borate glass is of great significance for optimizing and improving the luminous efficiency.The 2%molar ratio ...Erbium doped borate glass is widely used in luminescent materials,the luminescence dynamics of erbium doped borate glass is of great significance for optimizing and improving the luminous efficiency.The 2%molar ratio erbium doped borate glass was synthesized by the traditional melt quenching method,and annealed at 260℃below the borate glass transition temperature.The thermal performance parameters of borate glass undoped and doped with Er^(3+) were measured by differential scanning calorimetry with 10℃/min.The transient emission spectrum and decay kinetics curves were measured for the luminescence mechanism of erbium doped borate.Er^(3+) ions have different lifetime when emitted at 556 nm with different excitation wavelengths,the excited state trap may exist in erbium doped borate glass.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
By using two sections of erbium doped fiber and a fiber optical reflector, a novel, highly efficient L-band amplifier is demonstrated with significantly power-conversion-efficiency enhancement and the gain increasing ...By using two sections of erbium doped fiber and a fiber optical reflector, a novel, highly efficient L-band amplifier is demonstrated with significantly power-conversion-efficiency enhancement and the gain increasing of as much as 13 dB.展开更多
Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial...Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.展开更多
The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r...The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r Erbium doped alkali and alkaline earth phosphate glasses. It is found the comp ositional dependence of σ emi is almost similar to that of Σ abs, wh ich is determined by the sum of Ω t (3Ω 2+10Ω 4+21Ω 6). In addition, the compositional dependence of Ω t was studied in these glass systems. As a resu lt, compared with Ω 4 and Ω 6, the Ω 2 has a stronger compositional depend ence on the ionic radius and content of modifiers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, alumi nate glass, and tellurate glass, since Ω 6 of phosphate glass is relatively la rge. A R is affected by the covalency of the Er 3+ ion sites and correspon ds to the Ω 6 value.展开更多
Zinc oxide(ZnO) doped with erbium at different concentrations was synthesized by solid-state reaction method and characterized by X-ray diffraction(XRD), scanning electron microscopic(SEM), UVabsorption spectroscopy, ...Zinc oxide(ZnO) doped with erbium at different concentrations was synthesized by solid-state reaction method and characterized by X-ray diffraction(XRD), scanning electron microscopic(SEM), UVabsorption spectroscopy, photoluminescence(PL) study and vibrating sample magnetometer. The XRD studies exhibit the presence of wurtzite crystal structure similar to the parent compound ZnO in 1% Er^(3+)doped Zn O,suggesting that doped Er^(3+)ions sit at the regular Zn^(2+)sites. However, same studies spread over the samples with Er^(3+)content>1% reveals the occurrence of secondary phase. SEM images of 1% Er^(3+)doped ZnO show the polycrystalline nature of the synthesized sample. UV-visible absorption spectrum of Er^(3+)doped ZnO nanocrystals shows a strong absorption peak at 388 nm due to ZnO band to band transition. The PL study exhibits emission in the visible region, due to excitonic as well as defect related transitions. The magnetizationfield curve of Er^(3+)doped ZnO nanocrystals showed ferromagnetic property at room-temperature.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
A comprehensive behavioral investigation of gain and noise figure (NF) at different erbium doped fiber amplifier (EDFA) configurations is proposed. Configurations such as single pass (SP), single pass with filt...A comprehensive behavioral investigation of gain and noise figure (NF) at different erbium doped fiber amplifier (EDFA) configurations is proposed. Configurations such as single pass (SP), single pass with filter (SPF), double pass (DP) and double pass with filter (DPF) are designed, investigated and compared. A continuous increasing of gain value is recorded by changing the configuration from SP to SPF to DP then to DPF. The NF value shows different behaviors at different configurations.展开更多
In this paper, we propose a new design of all fiber optical switches by using a high finesse ring resonator (RR) side coupled Mach-Zehnder interferometer. We will show that by compensating the total loss in the RR the...In this paper, we propose a new design of all fiber optical switches by using a high finesse ring resonator (RR) side coupled Mach-Zehnder interferometer. We will show that by compensating the total loss in the RR the switching power can be decreased greatly and by loss, compensating the bistability effect in RR can be cancelled and the switching performance can be improved. In addition, we will show that by using Erbium doped fiber for fabricating the RR we can obtain switching power threshold in mW range.展开更多
Er^3+-doped phosphor-tellurite glass for broadband short-length Er^3+-doped fiber amplifier (EDFA) is fabricated and characterized. The differential value (AT) of onset crystalline temperature (Tx) and glass t...Er^3+-doped phosphor-tellurite glass for broadband short-length Er^3+-doped fiber amplifier (EDFA) is fabricated and characterized. The differential value (AT) of onset crystalline temperature (Tx) and glass transition temperature (Tg) is 206 ℃. The stimulated emission cross section of Er^3+ is calculated from absorption spectrum by McCumber theory and is 0.87 × 10 ^-20 cm^2 at 1532 nm. A broad 1.5-μm fluorescence spectrum with 54-nm full-width at half maximum (FWHM) is demonstrated. Especially, the maximum phonon energy of undoped phosphor-tellurite glass is 1100 cm^- 1, which restricts the upconversion luminescence. It is possible to pump efficiently at 980 nm. These results indicate Er^3+-doped phosphor-tellurite glass is suitable for fabricating broadband short-length EDFA.展开更多
LiEr0.02Fe0.98PO4/C composite cathode was synthesized by a simple solution method with polyethylene glycol (PEG) as the reductive agent and carbon source. The effect of erbium doping on the electrochemical behavior ...LiEr0.02Fe0.98PO4/C composite cathode was synthesized by a simple solution method with polyethylene glycol (PEG) as the reductive agent and carbon source. The effect of erbium doping on the electrochemical behavior of LiFePO4 was studied in this paper. The samples were characterized by X-ray powder diffraction and scanning electron microscopy and the electrochemical properties were investigated by the charge-discharge test. An initial discharge capacity of 149 mAh.g-1 was achieved for the LiEr0.02Fe0.98PO4/C composite cathode with a rate of 0.1 C. The electronic conductivity of Er doped LiFePO4/C was measured as 10-2 S.cm-1. The results indicated that erbium doping did not destroy the lattice structure of LiFePO4 and enlarge the lattice volume. These changes are beneficial to the improvement of the electrochemical performance of the LiFePO4 cathode.展开更多
文摘Erbium doped borate glass is widely used in luminescent materials,the luminescence dynamics of erbium doped borate glass is of great significance for optimizing and improving the luminous efficiency.The 2%molar ratio erbium doped borate glass was synthesized by the traditional melt quenching method,and annealed at 260℃below the borate glass transition temperature.The thermal performance parameters of borate glass undoped and doped with Er^(3+) were measured by differential scanning calorimetry with 10℃/min.The transient emission spectrum and decay kinetics curves were measured for the luminescence mechanism of erbium doped borate.Er^(3+) ions have different lifetime when emitted at 556 nm with different excitation wavelengths,the excited state trap may exist in erbium doped borate glass.
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By using two sections of erbium doped fiber and a fiber optical reflector, a novel, highly efficient L-band amplifier is demonstrated with significantly power-conversion-efficiency enhancement and the gain increasing of as much as 13 dB.
文摘Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.
基金Funded by the Natural Science Foundation of Guangdong Prov ince(013013) and the Science and Technology Plan of Guangdong Province(2002B11604)
文摘The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r Erbium doped alkali and alkaline earth phosphate glasses. It is found the comp ositional dependence of σ emi is almost similar to that of Σ abs, wh ich is determined by the sum of Ω t (3Ω 2+10Ω 4+21Ω 6). In addition, the compositional dependence of Ω t was studied in these glass systems. As a resu lt, compared with Ω 4 and Ω 6, the Ω 2 has a stronger compositional depend ence on the ionic radius and content of modifiers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, alumi nate glass, and tellurate glass, since Ω 6 of phosphate glass is relatively la rge. A R is affected by the covalency of the Er 3+ ion sites and correspon ds to the Ω 6 value.
文摘Zinc oxide(ZnO) doped with erbium at different concentrations was synthesized by solid-state reaction method and characterized by X-ray diffraction(XRD), scanning electron microscopic(SEM), UVabsorption spectroscopy, photoluminescence(PL) study and vibrating sample magnetometer. The XRD studies exhibit the presence of wurtzite crystal structure similar to the parent compound ZnO in 1% Er^(3+)doped Zn O,suggesting that doped Er^(3+)ions sit at the regular Zn^(2+)sites. However, same studies spread over the samples with Er^(3+)content>1% reveals the occurrence of secondary phase. SEM images of 1% Er^(3+)doped ZnO show the polycrystalline nature of the synthesized sample. UV-visible absorption spectrum of Er^(3+)doped ZnO nanocrystals shows a strong absorption peak at 388 nm due to ZnO band to band transition. The PL study exhibits emission in the visible region, due to excitonic as well as defect related transitions. The magnetizationfield curve of Er^(3+)doped ZnO nanocrystals showed ferromagnetic property at room-temperature.
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MMU and KFUPM/HBCC for their support in providing the various facilities utilized in the presentation of this paper
文摘A comprehensive behavioral investigation of gain and noise figure (NF) at different erbium doped fiber amplifier (EDFA) configurations is proposed. Configurations such as single pass (SP), single pass with filter (SPF), double pass (DP) and double pass with filter (DPF) are designed, investigated and compared. A continuous increasing of gain value is recorded by changing the configuration from SP to SPF to DP then to DPF. The NF value shows different behaviors at different configurations.
文摘In this paper, we propose a new design of all fiber optical switches by using a high finesse ring resonator (RR) side coupled Mach-Zehnder interferometer. We will show that by compensating the total loss in the RR the switching power can be decreased greatly and by loss, compensating the bistability effect in RR can be cancelled and the switching performance can be improved. In addition, we will show that by using Erbium doped fiber for fabricating the RR we can obtain switching power threshold in mW range.
基金the Instrument Science and Technology Opening Fund of Zhejiang Key Discipline(No.2006KF05)the National Natural Science Foundation of China(No.50502030 and 60508014).
文摘Er^3+-doped phosphor-tellurite glass for broadband short-length Er^3+-doped fiber amplifier (EDFA) is fabricated and characterized. The differential value (AT) of onset crystalline temperature (Tx) and glass transition temperature (Tg) is 206 ℃. The stimulated emission cross section of Er^3+ is calculated from absorption spectrum by McCumber theory and is 0.87 × 10 ^-20 cm^2 at 1532 nm. A broad 1.5-μm fluorescence spectrum with 54-nm full-width at half maximum (FWHM) is demonstrated. Especially, the maximum phonon energy of undoped phosphor-tellurite glass is 1100 cm^- 1, which restricts the upconversion luminescence. It is possible to pump efficiently at 980 nm. These results indicate Er^3+-doped phosphor-tellurite glass is suitable for fabricating broadband short-length EDFA.
基金supported by the Research Foundation of Erciyes University FBA-08-440 (Kayseri, Turkey)
文摘LiEr0.02Fe0.98PO4/C composite cathode was synthesized by a simple solution method with polyethylene glycol (PEG) as the reductive agent and carbon source. The effect of erbium doping on the electrochemical behavior of LiFePO4 was studied in this paper. The samples were characterized by X-ray powder diffraction and scanning electron microscopy and the electrochemical properties were investigated by the charge-discharge test. An initial discharge capacity of 149 mAh.g-1 was achieved for the LiEr0.02Fe0.98PO4/C composite cathode with a rate of 0.1 C. The electronic conductivity of Er doped LiFePO4/C was measured as 10-2 S.cm-1. The results indicated that erbium doping did not destroy the lattice structure of LiFePO4 and enlarge the lattice volume. These changes are beneficial to the improvement of the electrochemical performance of the LiFePO4 cathode.