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采用低压金属有机化合物气相沉积法(LP-MOCVD)生长并制作了1.6—1.7μm大应变InGaAs/InGaAsP分布反馈激光器.采用应变缓冲层技术,得到质量良好的大应变InGaAs/InP体材料.器件采用了4个大应变的量子阱,加入了载流子阻挡层改善器件的温度特性.1.66μm和1.74μm未镀膜的3μm脊型波导器件阈值电流低(小于15mA),输出功率高(100mA时大于14mW).从10—40℃,1.74μm激光器的特征温度T0=57K,和1.55μm InGaAsP分布反馈激光器的特征温度相当.
关键词:
MOCVD
InGaAs/InGaAsP
应变量子阱
分布反馈激光器 相似文献
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Wide-Band Polarization-Insensitive High-Output-Power Semiconductor Optical Amplifier Based on Thin Tensile-Strained Bulk InGaAs 总被引:2,自引:0,他引:2
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A polarization-insensitive semiconductor optical amplifier (SOA) with a very thin active tensile-strained InGaAs bu/k has been fabricated.The polarization sensitivity of the amplifier gain is less than 1 dB over both the entire range of driving current and the 3dB optical bandwidth of more than 8Onto.For optical signals of 1550nm wavelength,the SOA exhibits a high saturation output power 7.6dBm together with a low noise figure of 7.SdB, fibre-to-fibre gain of 11.5dB,and low polarization sensitivity of 0.5dB.Additionally,at the gain peak 1520nm,the fibre-to-fibre gain is measured to be 14.1 dB. 相似文献
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A kind of novel broad-band superluminescent diodes (SLDs) using graded tensile-strained bulk InGaAs is developed. The graded tensile-strained bulk InGaAs is obtained by changing only group-Ⅲ trimethylgallium source flow during low-pressure metal organic vapor-phase epitaxy. At the injection current of 200mA, the fabricated SLDs with such structure demonstrate full-width at half-maximum spectral width of 106 nm and the output light power of 13.6 mW, respectively. 相似文献
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Disappearance of Superconductivity and a Concomitant Lifshitz Transition in Heavily Overdoped Bi_2Sr_2CuO_6 Superconductor Revealed by Angle-Resolved Photoemission Spectroscopy
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丁颖 赵林 闫宏涛 高强 刘静 胡成 黄建伟 李聪 徐煜 蔡永青 戎洪涛 吴定松 宋春尧 周花雪 董晓莉 刘国东 王庆艳 张申金 王志敏 张丰丰 杨峰 彭钦军 许祖彦 陈创天 周兴江 《中国物理快报》2019,(1)
By partially doping Pb to effectively suppress the superstructure in single-layered cuprate Bi_2Sr_2CuO_(6+δ)(Pb-Bi2201) and annealing them in vacuum or in high pressure oxygen atmosphere, a series of high quality Pb-Bi2201 single crystals are obtained with T_c covering from 17 K to non-superconducting in the overdoped region. High resolution angle resolved photoemission spectroscopy measurements are carried out on these samples to investigate the evolution of the Fermi surface topology with doping in the normal state. Clear and complete Fermi surfaces are observed and quantitatively analyzed in all of these overdoped Pb-Bi2201 samples. A Lifshitz transition from holelike Fermi surface to electron-like Fermi surface with increasing doping is observed at a doping level of ~0.35. This transition coincides with the change that the sample undergoes superconducting-to-non-superconducting states.Our results reveal the emergence of an electron-like Fermi surface and the existence of a Lifshitz transition in heavily overdoped Bi2201 samples. This provides important information in understanding the connection between the disappearance of superconductivity and the Lifshitz transition in the overdoped region. 相似文献
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2005年高考重庆卷(理)压轴题为:数列{an}满足a1=1,且an 1=(1 1/(n2 n))an 1/2n(n≥1).(Ⅰ)用数学归纳法证明:an≥2(n≥2).(Ⅱ)已知不等式ln(1 x)0成立,证明:an0(k∈N*),∴由已知ln(1 x)0)有ln(1 1k2 k)<1k2 k,∴1 1k2 k相似文献
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利用活性亚结构拼接原理,设计制备了18个未见文献报道的新型含1,2,4-三唑环结构单元的吡唑肟醚衍生物.通过~1H NMR、~(13)C NMR和元素分析等手段确认了其结构.初步的生物活性测试结果表明,部分目标化合物对粘虫、蚜虫和朱砂叶螨表现出良好的杀灭效果.在测试浓度为500μg/m L时,目标化合物对粘虫的致死率在90%~100%,与对照药阿维菌素的杀虫效果相近,其中有4个化合物对蚜虫的致死率均为100%,与对照药吡虫啉的防效相当;1-甲基-3-甲基-5-(3,5-二氟苯氧基)-1H-吡唑-4-甲醛-O-[4-(1H-1,2,4-三唑-1-基)苯甲基]肟(8p)对朱砂叶螨的致死率为100%,与对照药唑螨酯的防效相当.当测试浓度降为100μg/m L时, 5个化合物对粘虫的致死率在90%~100%, 3个化合物对蚜虫的致死率在80%~100%;化合物8p对朱砂叶螨的致死率为80%.当测试浓度降至20μg/m L时, 2个化合物对粘虫的致死率分别为75%和70%.另外,部分化合物对人肝癌(SMMC-7721)细胞显示出一定的抗肿瘤活性. 相似文献