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排序方式: 共有397条查询结果,搜索用时 15 毫秒
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Stackable luminescent device integrating blue light emitting diode with red organic light emitting diode 下载免费PDF全文
We present a novel stackable luminescent device integrating a blue light emitting diode(LED)with a red organic LED(OLED)in series.The anode of the OLED is connected with the cathode of the LED through a via in the insulation layer on the LED.The LED–OLED hybrid device is electroluminescent and two electroluminescence(EL)peaks(the blue peak around 454 nm and the red peak around 610 nm)are observed clearly.The effect of the indium tin oxide(ITO)layer on the device performance is analyzed.Compared with the individual LED and OLED,their combination shows great potential applications in the field of white lighting,plant lighting,and display. 相似文献
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Period Continuous Tuning of an Efficient Mid-Infrared Optical Parametric Oscillator Based on a Fan-out Periodically Poled MgO-Doped Lithium Niobate 下载免费PDF全文
We report a period continuously tunable, efficient, mid-infrared optical parametric oscillator (OPO) based on a fan-out periodically poled MgO-doped congruent lithium niobate (PPMgLN). The OPO is pumped by a Nd:YAG laser and a maximum idler output average power of 1.65W at 3.93μm is obtained with a pump average power of 10.5W, corresponding to the conversion efficiency of about 16% from the pump to the idler. The output spectral properties of the OPO with the fan-out crystal are analyzed. The OPO is continuously tuned over 3.78-4.58μm (idler) when fan-out periods are changed from 27.0 to 29.4μm. Compared with temperature tuning, fan-out period continuous tuning has faster tuning rate and wider tuning range. 相似文献
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MBE生长高质量GaAs/AlGaAs量子阱激光器 总被引:6,自引:4,他引:2
我们利用分子束外延方法研制了GaAs/AlGaAs缓交折射率分别限制(GRIN-SCH)单量子阱和双量子阱激光器.对腔长为600μm的端面不镀膜的宽接触条型F-P腔激光器,阈值电流密度(平均值)分别为290A/cm2和240A/cm2.腔长在1200μm的双量子阱激光器的阈电流密度低达190A/cm2.对出光面和背面分别镀以增透膜和高反膜的宽接触条型(80μm).激光器,线性输出功率高达1.82W;出光面的斜率效率达到1.04W/A;利用湿法化学腐蚀所制备的脊形波导结构单量子阱激光器阈值电流最低可达8mA 相似文献
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Si(100)衬底上n-3C-SiC/p-Si异质结构研究 总被引:1,自引:1,他引:0
利用LPCVD方法在Si(100)衬底上获得了3C-SiC外延膜,扫描电子显微镜(SEM)研究表明3C-SiC/p-Si界面平整、光滑,无明显的坑洞形成。研究了以In和Al为接触电极的3C-SiC/p-Si异质结的I-V,C-V特性及I-V特性的温度依赖关系,比较了In电极的3C-SiC/p-Si异质结构和以SiGe作为缓冲层的3C-SiC/SiGe/p-Si异质结构的I-V特性,实验发现引入SiGe缓冲层后,器件的反向击穿电压由40V提高到70V以上。室温下Al电极3C-SiC/p-Si二极管的最大反向击穿电压接近100V,品质因子为1.95。 相似文献
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Mg-doped AlGaN and GaN/AlGaN superlattices are grown by metalorganic chemical vapour deposition (MOCVD) Rapid thermal annealing (RTA) treatments are carried out on the samples. Hall and high resolution x-ray diffraction measurements are used to characterize the electrical and structural prosperities of the as-grown and annealed samples, respectively. The results of hall measurements show that after annealing, the Mg-doped AIGaN sample can not obtain the distinct hole concentration and can acquire a resistivity of 1.4 ×10^3 Ωcm. However, with the same annealing treatment, the GaN/AlGaN superlattice sample has a hole concentration of 1.7 × 10^17 cm-3 and a resistivity of 5.6Ωcm. The piezoelectric field in the GaN/AlGaN superlattices improves the activation efficiency of Mg acceptors, which leads to higher hole concentration and lower p-type resistivity. 相似文献
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