【摘 要】
：
Ultraviolet (UV) detectors with large photosensitive areas are more advantageous in low-level UV detection applications. In this Letter, high-performance 4H-SiC p-i-n avalanche photodiodes (APDs) with large active area (800 μm diameter) are reported. With
【机 构】
：
NationalKeyLaboratoryofASIC,HebeiSemiconductorResearchInstitute,Shijiazhuang050051,China
【出 处】
：
ChineseOpticsLetters
论文部分内容阅读
Ultraviolet (UV) detectors with large photosensitive areas are more advantageous in low-level UV detection applications. In this Letter, high-performance 4H-SiC p-i-n avalanche photodiodes (APDs) with large active area (800 μm diameter) are reported. With the optimized epitaxial structure and device fabrication process, a high multiplication gain of 1.4 × 106 is obtained for the devices at room temperature, and the dark current is as low as ～10 pA at low reverse voltages. In addition, record external quantum efficiency of 85.5% at 274 nm is achieved, which is the highest value for the reported SiC APDs. Furthermore, the rejection ratio of UV to visible light reaches about 104. The excellent performance of our devices indicates a tremendous improvement for large-area SiC APD-based UV detectors. Finally, the UV imaging performance of our fabricated 4H-SiC p-i-n APDs is also demonstrated for system-level applications.
其他文献
提出了一种易研制的高双折射双零色散波长新型光子晶体光纤。其包层由采用2种不同尺寸的圆形空气孔按照类矩形和三角形晶格排列而成。运用全矢量有限元法对其光学特性进行理论模拟分析, 结果表明, 当d1=0.80 μm, d2=1.10 μm, Λ=1.00 μm时, 在1.55 μm波长处获得2.59×10-2的双折射, 且在X、Y偏振方向的非线性系数分别为46 km-1·W-1和36 km-1·W-1。同时, 该光纤在可见光和近红外波段具有2个零色散点, 色散点间距为0.68 μm。通过设置合理的参数, 双零色
Thermally regenerated low-reflectivity fiber Bragg gratings (RFBGs), as one mirror of a resonant cavity, have been introduced as linear-cavity fiber lasers combining with fiber saturable absorbers. The output of lasing presents an optical signal-to-noise
由于人眼看不见红外激光辐射，故当红外激光器工作时，要建立所需振荡波型和调节仪器都发生困难。下面叙述直接用眼睛观察这类激光辐射场图案的方法，这一方法的依据是增强被辐照磷光体的余辉的强度。
本器件以连续FM锁模工作,利用非正弦调制实现了相锁态的分离,可长期稳定运转.脉宽66ps,带宽10.6GHz;脉冲幅稳度±3%.平均功率200mW.最大带宽可达15.6GHz,相应脉宽小于50ps.
为了解决数字图像亚像素级高精度尺寸检测问题,采用了基于人工神经网络的线阵相机镜头畸变矫正方法,比传统的多项式拟合法矫正精度高且操作简便;提出了将光栅尺融入线阵相机扫描机构的新方法,利用高精度光栅尺测位移信号触发线阵CCD图像采集动作,精确获取线阵相机扫描目标的亚像素级图像。实验证明,新的测量技术可在对运动系统要求不高的情况下获取高精度图像,图像检测精度可以达到1μm。
In this Letter, we reported the preliminary results of an integrating periodically capacitive-loaded traveling wave electrode (CL-TWE) Mach–Zehnder modulator (MZM) based on InP-based multiple quantum well (MQW) optical waveguides. The device configuration
以Gd原子999 cm-1亚稳态为初始能级,用共振多光子电离(RMPI)方法研究了Gd原子在34463～35628 cm-1范围内的高激发态。实验共测得19个高激发能级。
A numerical design on the triangular photonic crystal fiber (PCF) based backward multi-pump Raman amplifier is presented. It is demonstrated that high flat Raman gain can be reached based on PCF. Influences of different geometric parameters and germanium