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
In this work, performance enhancements of amplified spontaneous emission （ASE） from poly[2-methoxy-5-（2＇- ethyl-hexyloxy）-l,4-phenylene vinylene] （MEH-PPV） have been achieved via solvent vapour treatment. Corre...In this work, performance enhancements of amplified spontaneous emission （ASE） from poly[2-methoxy-5-（2＇- ethyl-hexyloxy）-l,4-phenylene vinylene] （MEH-PPV） have been achieved via solvent vapour treatment. Correlations between the morphology of the film and the optical performance of polymer-based ASE are investigated. The active layers are characterised by atomic force microscopy and optical absorption. The results show that the solvent-vapour treatment can induce the MEH-PPV self-organisation into an ordered structure with a smooth surface, leading to enhanced optical gain. Thus the solvent-vapour treatment is a good method for improving the optical properties of the MEH-PPV.展开更多
Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.Howe...Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.However,two-photon pumped amplified spontaneous emission(ASE)and the corresponding nonlinear optical properties of FAPbBr_(3) NCs are scarcely revealed.Herein,we synthesized colloidal FAPbBr_(3) NCs with different sizes by changing the molar ratio of FABr/PbBr_(2) in the precursor solution,using ligand assisted precipitation(LARP)technology at room temperature.Photoluminescence(PL)and time resolved photoluminescence(TRPL)spectroscopy were measured to characterize their ASE properties.And their nonlinear optical properties were studied through the Zscan technique and the two-photon excited fluorescence method.The stimulated emission properties including oneand two-photon pumped ASE have been realized from FAPbBr_(3) NCs.With large two-photon absorption coefficient(0.27 cm/GW)and high non-linear absorption cross-section(7.52×10^(5) GM),ASE with threshold as low as 9.8μJ/cm^(2) and 487μJ/cm^(2) have been obtained from colloidal FAPbBr_(3) NCs using one-and two-photon excitations.These results indicate that as a new possible green-emitting frequency-upconversion material with low thresholds,FAPbBr_(3) NCs hold great potential in the development of high-performance two-photon pump lasers.展开更多
This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the...This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the range 1450-1650 nm from erbium-doped single-mode tellurite glass-fibre is obtained upon excitation of a 980-nm laser diode. The effects of the length of glass-fibre and the pumping power of laser diode on the amplified spontaneous emission are discussed. The result indicates that the tellurite glass-fibre is a promising candidate for designing fibre-optic amplifiers and lasers.展开更多
A model of three-level amplified spontaneous emission(ASE)sources,considering radiation effect,is proposed to predict radiation induced loss of output power in radiation environment.Radiation absorption parameters of ...A model of three-level amplified spontaneous emission(ASE)sources,considering radiation effect,is proposed to predict radiation induced loss of output power in radiation environment.Radiation absorption parameters of ASE sources model are obtained by the fitting of color centers generation and recovery process of gain loss data at lower dose rate.Gain loss data at higher dose is applied for self-validating.This model takes both the influence of erbium ions absorption and photon bleaching effect into consideration,which makes the prediction of different dose and dose rate more accurate and flexible.The fitness value between ASE model and gain loss data is 99.98%,which also satisfies the extrapolation at the low dose rate.The method and model may serve as a valuable tool to predict ASE performance in harsh environment.展开更多
Amplified spontaneous emission （ASE）, including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental mea...Amplified spontaneous emission （ASE）, including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental measurements of a BuEH-PPV sample pumped at different pump intensities from Ip = 0.61 MW/cm2 to 5.2 MW/cm2. Both homogeneously and inhomogeneously broadened transition lines along with a model based on the geometrically dependent gain coefficient （GDGC） are examined and it is confirmed that for the reported measurements the homogeneously broadened line is responsible for the light-matter interaction. The calculation explains the frequency spectrum of the ASE output intensity extracted from the sample at different pump intensities, unsaturated and saturated gain coefficients, and ASE bandwidth reduction along the propagation direction. Both analytical and numerical calculations for verifying the GDGC model are presented in this paper. Although the introduced model has shown its potential for explaining the ASE behavior in a specific sample it can be universally used for the ASE study in different active media.展开更多
We investigate the effect of a metallic electrode on the ability for poly[2-methoxy-5-（2＇-ethylhexyloxy）-1,4- phenylene vinylene] （MEH-PPV） film to undergo amplified spontaneous emission （ASE）. The threshold of...We investigate the effect of a metallic electrode on the ability for poly[2-methoxy-5-（2＇-ethylhexyloxy）-1,4- phenylene vinylene] （MEH-PPV） film to undergo amplified spontaneous emission （ASE）. The threshold of the device with Ag cladding is about 10 times greater than that of a metal-free device, but metal such as Al completely shuts off ASE. The ASE recurs when a thin spacer layer, such as a few nanometers of SiO2, is introduced between the MEH-PPV film and the Al cladding. Compared with the Cu or Al electrode, the Ag cladding is most suited to serve as an electrode with its low optical loss due to its high work-function and reflectivity.展开更多
We investigate the amplified spontaneous emission （ASE） from an Ag-backed poly[2-methoxy-5-（2＇-ethylhexyloxy）- 1,4-phenylenevinylene] （MEH-PPV） film with different film thicknesses. The ASE characteristics of A...We investigate the amplified spontaneous emission （ASE） from an Ag-backed poly[2-methoxy-5-（2＇-ethylhexyloxy）- 1,4-phenylenevinylene] （MEH-PPV） film with different film thicknesses. The ASE characteristics of Ag-backed MEH- PPV films with different thicknesses show that increasing the film thickness can reduce the influence of the Ag cladding. The threshold, the gain, and the loss of the device with a thickness of 170 nm are comparable to those of a metal-free device. The lasing threshold of this device is about 7.5 times that of a metal-free device. Our findings demonstrate that Ag-backed MEH-PPV film with an appropriate thickness can still be a good polymer gain material for the fabrication of solid-state lasers.展开更多
Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation result...Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation results confirm that ASE noise in the Raman wavelength band could reduce the SRS threshold of high-power fiber amplifiers significantly.As for ASE noise originated the main amplifier,it becomes stronger and reduces the SRS threshold at shorter operation wavelength below 1052 nm.As for ASE noise originated from the seed laser,it reduces the SRS threshold at different operation wavelength under the condition that the Raman ratio is over-90 dB in the seed laser.The theoretical method and results in this work could provide a well reference to extend the operation wavelength of high-power fiber lasers.展开更多
Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves....Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.展开更多
根据三轴光纤陀螺的高精度需求,采用大功率高稳定性的高精度双程后向方案掺铒光纤光源。通过对ASE光源的理论分析建立数学模型,并根据所用掺铒光纤及泵浦光源的参数对光源进行谱型分析,确定光路方案。再以掺铒光纤和泵浦激光器的温度特...根据三轴光纤陀螺的高精度需求,采用大功率高稳定性的高精度双程后向方案掺铒光纤光源。通过对ASE光源的理论分析建立数学模型,并根据所用掺铒光纤及泵浦光源的参数对光源进行谱型分析,确定光路方案。再以掺铒光纤和泵浦激光器的温度特性和补偿为研究重点,对掺铒光纤的长度和掺杂浓度以及泵浦功率和铒纤的匹配性进行试验,最终采用铒纤长度19 m,泵浦波长974.6 nm,泵浦功率140 m A,得到光源光功率为20 m W,平均波长变化量小于0.5′10^(-6)/℃,满足光纤陀螺对ASE光源的要求。展开更多
Carrier recovery time is a key parameter that determines the performance of a semiconductor optical amplifier （SOA）. A measurement method of carrier recovery time in SOA based on a nearly degenerate four-wave mixing...Carrier recovery time is a key parameter that determines the performance of a semiconductor optical amplifier （SOA）. A measurement method of carrier recovery time in SOA based on a nearly degenerate four-wave mixing of narrowband amplified spontaneous emission （ASE） spectra is presented. The results show the carrier times are 50.2, 44.6, and 23.6 ps when the injected currents are 120, 180, and 240 mA, respectively, which are in agreement with the nominal values of the sample.展开更多
The influence of pumping laser pulse on the property of quasi-continuous-wave(QCW)diode-side-pumped Nd:YAG laser is investigated theoretically and experimentally.Under remaining a fixed duty cycle,the average output p...The influence of pumping laser pulse on the property of quasi-continuous-wave(QCW)diode-side-pumped Nd:YAG laser is investigated theoretically and experimentally.Under remaining a fixed duty cycle,the average output power increases,and the corresponding thermal focal length shorten with the increase of the pump pulse duration,which attributes to the decrease of the ratio of pulse buildup time to the pulse duration.At a pump power of 146 W,the laser output power changes from 65.1 W to 81.2 W when the pulse duration is adjusted from 150μs to 1000μs,confirming a significant enhancement of 24.7%.A laser rate equation model incorporating the amplified spontaneous emission is also utilized and numerically solved,and the simulated results agree well with the experimental data.展开更多
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.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.60978061,60777026,60677007 and 60825407)the Program for New Century Excellent Talents in University of China(Grant No.NCET-08-0717)+1 种基金the Beijing Municipal Science and Technology Commission of China(Grant Nos.Z090803044009001 and 4102046)the Program of Introducing Talents of Discipline to Universities,China(Grant No.B08002)
文摘In this work, performance enhancements of amplified spontaneous emission （ASE） from poly[2-methoxy-5-（2＇- ethyl-hexyloxy）-l,4-phenylene vinylene] （MEH-PPV） have been achieved via solvent vapour treatment. Correlations between the morphology of the film and the optical performance of polymer-based ASE are investigated. The active layers are characterised by atomic force microscopy and optical absorption. The results show that the solvent-vapour treatment can induce the MEH-PPV self-organisation into an ordered structure with a smooth surface, leading to enhanced optical gain. Thus the solvent-vapour treatment is a good method for improving the optical properties of the MEH-PPV.
文摘Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.However,two-photon pumped amplified spontaneous emission(ASE)and the corresponding nonlinear optical properties of FAPbBr_(3) NCs are scarcely revealed.Herein,we synthesized colloidal FAPbBr_(3) NCs with different sizes by changing the molar ratio of FABr/PbBr_(2) in the precursor solution,using ligand assisted precipitation(LARP)technology at room temperature.Photoluminescence(PL)and time resolved photoluminescence(TRPL)spectroscopy were measured to characterize their ASE properties.And their nonlinear optical properties were studied through the Zscan technique and the two-photon excited fluorescence method.The stimulated emission properties including oneand two-photon pumped ASE have been realized from FAPbBr_(3) NCs.With large two-photon absorption coefficient(0.27 cm/GW)and high non-linear absorption cross-section(7.52×10^(5) GM),ASE with threshold as low as 9.8μJ/cm^(2) and 487μJ/cm^(2) have been obtained from colloidal FAPbBr_(3) NCs using one-and two-photon excitations.These results indicate that as a new possible green-emitting frequency-upconversion material with low thresholds,FAPbBr_(3) NCs hold great potential in the development of high-performance two-photon pump lasers.
基金Project supported by the National Natural Science Foundation 0f China （Grant Nos 50472053 and 60307004）, National Century Elitist Table （Grant Nos 04-0821 and 04-0823） and Natural Science Foundation of Guangdong Province. （Grant Nos 04020036 and 2004A10602002）.Acknowledgments We are grateful to Mrs Zhang W N, Feng Z M, Chen H and Chen B Y for their technical assistance.
文摘This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μm optical amplifiers. A very broad erbium amplified spontaneous emission in the range 1450-1650 nm from erbium-doped single-mode tellurite glass-fibre is obtained upon excitation of a 980-nm laser diode. The effects of the length of glass-fibre and the pumping power of laser diode on the amplified spontaneous emission are discussed. The result indicates that the tellurite glass-fibre is a promising candidate for designing fibre-optic amplifiers and lasers.
基金supported by the Aeronautical Science Foundation of China(Grant No.20170851007)。
文摘A model of three-level amplified spontaneous emission(ASE)sources,considering radiation effect,is proposed to predict radiation induced loss of output power in radiation environment.Radiation absorption parameters of ASE sources model are obtained by the fitting of color centers generation and recovery process of gain loss data at lower dose rate.Gain loss data at higher dose is applied for self-validating.This model takes both the influence of erbium ions absorption and photon bleaching effect into consideration,which makes the prediction of different dose and dose rate more accurate and flexible.The fitness value between ASE model and gain loss data is 99.98%,which also satisfies the extrapolation at the low dose rate.The method and model may serve as a valuable tool to predict ASE performance in harsh environment.
文摘Amplified spontaneous emission （ASE）, including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental measurements of a BuEH-PPV sample pumped at different pump intensities from Ip = 0.61 MW/cm2 to 5.2 MW/cm2. Both homogeneously and inhomogeneously broadened transition lines along with a model based on the geometrically dependent gain coefficient （GDGC） are examined and it is confirmed that for the reported measurements the homogeneously broadened line is responsible for the light-matter interaction. The calculation explains the frequency spectrum of the ASE output intensity extracted from the sample at different pump intensities, unsaturated and saturated gain coefficients, and ASE bandwidth reduction along the propagation direction. Both analytical and numerical calculations for verifying the GDGC model are presented in this paper. Although the introduced model has shown its potential for explaining the ASE behavior in a specific sample it can be universally used for the ASE study in different active media.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60978061,60777026,60677007,60825407,and 61036007)the Program for New Century Excellent Talents in University,China (Grant No. NCET-08-0717)+1 种基金the Beijing Municipal Science and Technology Commission (Grant Nos. Z090803044009001 and 4102046)the Program of Introducing Talents of Discipline to Universities,China (Grant No. B08002)
文摘We investigate the effect of a metallic electrode on the ability for poly[2-methoxy-5-（2＇-ethylhexyloxy）-1,4- phenylene vinylene] （MEH-PPV） film to undergo amplified spontaneous emission （ASE）. The threshold of the device with Ag cladding is about 10 times greater than that of a metal-free device, but metal such as Al completely shuts off ASE. The ASE recurs when a thin spacer layer, such as a few nanometers of SiO2, is introduced between the MEH-PPV film and the Al cladding. Compared with the Cu or Al electrode, the Ag cladding is most suited to serve as an electrode with its low optical loss due to its high work-function and reflectivity.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.60978061,60777026,60677007,and 60825407)the Program for New Century Excellent Talents in University of China (Grant No.NCET-08-0717)+1 种基金the Beijing Municipal Science and Technology Commission of China (Grant Nos.Z090803044009001 and 4102046)the Program of Introducing Talents of Discipline to Universities,China (Grant No.B08002)
文摘We investigate the amplified spontaneous emission （ASE） from an Ag-backed poly[2-methoxy-5-（2＇-ethylhexyloxy）- 1,4-phenylenevinylene] （MEH-PPV） film with different film thicknesses. The ASE characteristics of Ag-backed MEH- PPV films with different thicknesses show that increasing the film thickness can reduce the influence of the Ag cladding. The threshold, the gain, and the loss of the device with a thickness of 170 nm are comparable to those of a metal-free device. The lasing threshold of this device is about 7.5 times that of a metal-free device. Our findings demonstrate that Ag-backed MEH-PPV film with an appropriate thickness can still be a good polymer gain material for the fabrication of solid-state lasers.
基金the National Natural Science Foundation of China(Grant Nos.62005313 and 62061136013).
文摘Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation results confirm that ASE noise in the Raman wavelength band could reduce the SRS threshold of high-power fiber amplifiers significantly.As for ASE noise originated the main amplifier,it becomes stronger and reduces the SRS threshold at shorter operation wavelength below 1052 nm.As for ASE noise originated from the seed laser,it reduces the SRS threshold at different operation wavelength under the condition that the Raman ratio is over-90 dB in the seed laser.The theoretical method and results in this work could provide a well reference to extend the operation wavelength of high-power fiber lasers.
基金financial supports from National Natural Science Foundation of China(No.61905051)Natural Science Foundation of Heilongjiang Province(No.LH2020F027).
文摘Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.
文摘根据三轴光纤陀螺的高精度需求,采用大功率高稳定性的高精度双程后向方案掺铒光纤光源。通过对ASE光源的理论分析建立数学模型,并根据所用掺铒光纤及泵浦光源的参数对光源进行谱型分析,确定光路方案。再以掺铒光纤和泵浦激光器的温度特性和补偿为研究重点,对掺铒光纤的长度和掺杂浓度以及泵浦功率和铒纤的匹配性进行试验,最终采用铒纤长度19 m,泵浦波长974.6 nm,泵浦功率140 m A,得到光源光功率为20 m W,平均波长变化量小于0.5′10^(-6)/℃,满足光纤陀螺对ASE光源的要求。
基金Project supported by National High Technology Research and Development Program of China (Grant No. 2006AA03Z414)the National Natural Science Foundation of China (Grant No. 60877056)the Science Fund for Distinguished Young Scholars of Hubei Province of China (Grant No. 2006ABB017)
文摘Carrier recovery time is a key parameter that determines the performance of a semiconductor optical amplifier （SOA）. A measurement method of carrier recovery time in SOA based on a nearly degenerate four-wave mixing of narrowband amplified spontaneous emission （ASE） spectra is presented. The results show the carrier times are 50.2, 44.6, and 23.6 ps when the injected currents are 120, 180, and 240 mA, respectively, which are in agreement with the nominal values of the sample.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0402103)the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.GJJSTD20180004)the Fund of Technical Institute of Physics and Chemistry,Chinese Academy of Sciences(Grant No.Y8A9021H11)。
文摘The influence of pumping laser pulse on the property of quasi-continuous-wave(QCW)diode-side-pumped Nd:YAG laser is investigated theoretically and experimentally.Under remaining a fixed duty cycle,the average output power increases,and the corresponding thermal focal length shorten with the increase of the pump pulse duration,which attributes to the decrease of the ratio of pulse buildup time to the pulse duration.At a pump power of 146 W,the laser output power changes from 65.1 W to 81.2 W when the pulse duration is adjusted from 150μs to 1000μs,confirming a significant enhancement of 24.7%.A laser rate equation model incorporating the amplified spontaneous emission is also utilized and numerically solved,and the simulated results agree well with the experimental data.
