【摘 要】
：
In this paper, a slot microring resonator with a piece of spiral feedback waveguide for CH4 sensing application is pro-posed. This sensor is based on silicon-on-insulator (SOI) substrate and with the operation wavelength in mid-infrared region. To reach h
【机 构】
：
FacultyofElectricalEngineeringandComputerScience,NingboUniversity,Ningbo315211,China
【出 处】
：
OptoelectronicsLetters
论文部分内容阅读
In this paper, a slot microring resonator with a piece of spiral feedback waveguide for CH4 sensing application is pro-posed. This sensor is based on silicon-on-insulator (SOI) substrate and with the operation wavelength in mid-infrared region. To reach high sensitivity and good selectivity, slot cross section and spiral feedback waveguide are carefully tailored. The sensor shows ppb-scale trace gas sensing potential and is easy to be packaged in integrated photonics circuits. Calculation results show that the sensitivity reaches 1.4×10-2 dB/ppm and the detection limit achieves 700 ppb in the case of Lspiral=100Lr.
其他文献
A method of chromatic polarization imaging is presented for the online detection of colorless plastic contaminants from ginned cotton in an industrial setting. To understand the experimental results, we consider a realistic microscopic model, including th
本文首次报道了用共振多光子电离(RMPI)技术探测到四条在可见光范围内的Gd原子强双光子跃迁线.观察到双色三光子Gd原子激光同位素分离.研究了高分辨率Gd原子电离谱,并解释了电离谱的线型.
Recent advances in experimental techniques and data processing allow in situ determination of mineral crystal structure and chemistry up to Mbar pressures in a laser-heated diamond anvil cell (DAC), providing the fundamental information of the mineralogic
针对结构光测量中条纹灰度非对称分布使条纹中心提取精度降低的问题，提出了一种应用于条纹中心提取的条纹灰度非对称调整方法。首先对初始灰度进行幂运算，将初始灰度和幂运算结果相减，并对相减结果进行灰度补偿，然后利用补偿后的灰度再进行迭代，直至满足迭代终止条件。此外，分析了条纹灰度非对称分布的影响因素，提出了条纹灰度分布的评价参数，并对所提方法进行了实验验证。实验结果表明，该方法可以根据条纹灰度的初始分布情况对条纹灰度进行有效调整，迭代结果突出了最大值附近的灰度信息，降低了灰度非对称分布对条纹中心提取的影响，提高了
在光子相关光谱(PCS)颗粒测量技术中非线性累积反演方法是一种重要的算法。采用无约束非线性优化算法对反演过程中相关曲线的拟合问题进行了分析和研究, 实现了从任意初始值开始获取最优非线性拟合解, 并给出了算法的实现步骤。采用此方法对50 nm, 100 nm, 200 nm和500 nm的标准聚苯乙烯乳胶颗粒的实测光强自相关函数数据进行了拟合, 并反演了颗粒粒径, 与其他曲线拟合算法相比, 本算法不但对初始值的依赖性小, 而且得到的颗粒粒径更接近乳胶颗粒的标称直径, 测量误差更小。
针对多角度偏振成像仪探测器光电性能的评估需求,研制一套图像传感器光电性能参数通用测试系统,并提出一种基于珀耳帖效应的热电制冷器和低温循环机相组合的探测器控温方法。实验结果表明积分球的光源稳定性为0.036%,照度均匀度≥99.3%,探测器制冷系统降温速率约为2.2 ℃/min,温控精度优于±0.15 ℃,实现在-10~25 ℃的工作温度范围内对量子效率、光响应不一致性、暗电流、满阱电荷和光响应非线性等关键性能参数的测量,多角度偏振成像仪探测器不同波长下的光响应不一致性优于3%,光响应非线性优于1%,工作温
We investigate femtosecond laser trapping dynamics of two-photon absorbing hollow-core nanoparticles with different volume fractions and two-photon absorption (TPA) coefficients. Numerical simulations show that the hollow-core particles with low and high-
Tongue cancer is an increasingly common disease with high morbidity. Besides clinical observation, biomedical imaging techniques have been investigated for early detection of tongue cancer. In this paper, we proposed a co-registered dual-modality photoaco