Electroluminescence (EL) and temperature-dependent photolumineseenee measurements are performed to study the internal quantum efficiency droop phenomenon of blue laser diodes (LDs) before lasing. Based on the ABC ...Electroluminescence (EL) and temperature-dependent photolumineseenee measurements are performed to study the internal quantum efficiency droop phenomenon of blue laser diodes (LDs) before lasing. Based on the ABC mode, the EL result demonstrates that non-radiative recombination rates of LDs with threshold current densities of 4 and 6kA/cm2 are similar, while LD with threshold current density of 4kA/cm2 exhibits a smaller auger- like recombination rate compared with the one of 6kA/cm2. The internal quantum efficiency droop is more serious for LD with higher threshold current density. temperature-dependent photoluminescence is consistent The internal quantum efficiency value estimated from with EL measurements.展开更多
A tunable single-passband microwave photonic filter is proposed and demonstrated, based on a laser diode (LD) array with multiple optical carriers and a Fabry-Perot (F-P) laser diode. Multiple optical carriers in conj...A tunable single-passband microwave photonic filter is proposed and demonstrated, based on a laser diode (LD) array with multiple optical carriers and a Fabry-Perot (F-P) laser diode. Multiple optical carriers in conjunction with the F-P LD will realize a filter with multiple passbands. By adjusting the wavelengths of the multiple optical carriers, multiple passbands are merged into a single passband with a broadened bandwidth. By varying the number of the optical carrier, the bandwidth can be adjusted. The central frequency can be tuned by adjusting the wavelength of the multiple optical carriers simultaneously. A single-passband filter implemented by two optical carriers is experimentally demonstrated.展开更多
A fiber-coupled laser-diode (LD) end-pumped Nd:GdVO4 slab continuous-wave (CW) 912-nm laser and an LD bar end-pumped Nd:GdVO4 slab CW 912-nm laser are both demonstrated in this paper. Using the fiber-coupled LD ...A fiber-coupled laser-diode (LD) end-pumped Nd:GdVO4 slab continuous-wave (CW) 912-nm laser and an LD bar end-pumped Nd:GdVO4 slab CW 912-nm laser are both demonstrated in this paper. Using the fiber-coupled LD of end-pumped type, a highest CW 912-nm laser output power of 10.17 W is obtained with a high optical to-optical conversion efficiency of 24.6% and a slope efficiency of 34.5%. The measured M2 factors of beam quality in x and y directions are 5.3 and 5.1, respectively. Besides, an LD bar of end-pumped type is used to realize CW 912-nm laser output, which has the advantages of compactness and low cost. When the pump power is 38.8 W, the output power is 8.87 W and the measured M^2 factors of beam quality in x and y directions are 16 and 1.31, respectively. In order to improve the beam quality of the 912-nm laser at x direction, a new quasi-concentric laser resonator will be designed, and an LD bar end-pumped Nd:GdVO4 slab high-power CW 912-nm TEM00 laser will be realized in the future.展开更多
光栅结构的设计和制作直接决定了分布反馈(DFB)半导体激光器光电特性的优劣。采用传输矩阵法模拟了不同光栅耦合因子下随机相位对均匀光栅DFB芯片特性的影响,获得了芯片的光电参数分布。通过分析耦合因子对芯片光电参数分布的影响,提...光栅结构的设计和制作直接决定了分布反馈(DFB)半导体激光器光电特性的优劣。采用传输矩阵法模拟了不同光栅耦合因子下随机相位对均匀光栅DFB芯片特性的影响,获得了芯片的光电参数分布。通过分析耦合因子对芯片光电参数分布的影响,提高了DFB芯片的成品率。设计并制备了基于Al Ga In As材料体系的脊波导DFB激光器,最终使芯片双峰比例仅为7.7%、成品率达到60%。对合格品在-40~105℃下的P-I特性和在-40~85℃下的光谱进行了测试,结果表明芯片性能优良,芯片远场发散角为25°和21°。芯片的小信号频带响应和眼图测试结果表明芯片完全满足2.5 Gbit/s的应用要求。展开更多
基金Supported by the National Key Research and Development Program of China under Grant Nos 2016YFB0401803 and 2016YFB0402002the National Natural Science Foundation of China under Grant Nos 61574160 and 61334005+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDA09020401the Visiting Professorship for Senior International Scientists of the Chinese Academy of Sciences under Grant No 2013T2J0048
文摘Electroluminescence (EL) and temperature-dependent photolumineseenee measurements are performed to study the internal quantum efficiency droop phenomenon of blue laser diodes (LDs) before lasing. Based on the ABC mode, the EL result demonstrates that non-radiative recombination rates of LDs with threshold current densities of 4 and 6kA/cm2 are similar, while LD with threshold current density of 4kA/cm2 exhibits a smaller auger- like recombination rate compared with the one of 6kA/cm2. The internal quantum efficiency droop is more serious for LD with higher threshold current density. temperature-dependent photoluminescence is consistent The internal quantum efficiency value estimated from with EL measurements.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61302026,61275067 and 61575034the Jiangsu Natural Science Foundation under Grant No BK2012432
文摘A tunable single-passband microwave photonic filter is proposed and demonstrated, based on a laser diode (LD) array with multiple optical carriers and a Fabry-Perot (F-P) laser diode. Multiple optical carriers in conjunction with the F-P LD will realize a filter with multiple passbands. By adjusting the wavelengths of the multiple optical carriers, multiple passbands are merged into a single passband with a broadened bandwidth. By varying the number of the optical carrier, the bandwidth can be adjusted. The central frequency can be tuned by adjusting the wavelength of the multiple optical carriers simultaneously. A single-passband filter implemented by two optical carriers is experimentally demonstrated.
文摘A fiber-coupled laser-diode (LD) end-pumped Nd:GdVO4 slab continuous-wave (CW) 912-nm laser and an LD bar end-pumped Nd:GdVO4 slab CW 912-nm laser are both demonstrated in this paper. Using the fiber-coupled LD of end-pumped type, a highest CW 912-nm laser output power of 10.17 W is obtained with a high optical to-optical conversion efficiency of 24.6% and a slope efficiency of 34.5%. The measured M2 factors of beam quality in x and y directions are 5.3 and 5.1, respectively. Besides, an LD bar of end-pumped type is used to realize CW 912-nm laser output, which has the advantages of compactness and low cost. When the pump power is 38.8 W, the output power is 8.87 W and the measured M^2 factors of beam quality in x and y directions are 16 and 1.31, respectively. In order to improve the beam quality of the 912-nm laser at x direction, a new quasi-concentric laser resonator will be designed, and an LD bar end-pumped Nd:GdVO4 slab high-power CW 912-nm TEM00 laser will be realized in the future.
文摘光栅结构的设计和制作直接决定了分布反馈(DFB)半导体激光器光电特性的优劣。采用传输矩阵法模拟了不同光栅耦合因子下随机相位对均匀光栅DFB芯片特性的影响,获得了芯片的光电参数分布。通过分析耦合因子对芯片光电参数分布的影响,提高了DFB芯片的成品率。设计并制备了基于Al Ga In As材料体系的脊波导DFB激光器,最终使芯片双峰比例仅为7.7%、成品率达到60%。对合格品在-40~105℃下的P-I特性和在-40~85℃下的光谱进行了测试,结果表明芯片性能优良,芯片远场发散角为25°和21°。芯片的小信号频带响应和眼图测试结果表明芯片完全满足2.5 Gbit/s的应用要求。