A Mach-Zehnder interferometer electro-optic switch with ultralow voltage-length product using poled-polymer/ silicon slot waveguide

By using poled-polymer/silicon slot waveguides in the active region and the Pockels effect of the poled-polymer, we propose a kind of Mach-Zehnder interferometer (MZI) electro-optic (EO) switch operated at 1 550 nm. Structural parameters are optimized for realizing normal switching function. Dependencies of switching characteristics on the slot waveguide parameters are investigated. For the silicon strip with dimension of 170 nm×300 nm, as the slot width varies from 50 nm to 100 nm, the switching voltage can be as low as 1.0 V with active region length of only 0.17–0.35 mm, and the length of the whole device is only about 770–950 μm. The voltage-length product of this switching structure is only 0.17–0.35 V.mm, and it is at least 19–40 times smaller than that of the traditional polymer MZI EO switch, which is 6.69 V.mm. Compared with our previously reported MZI EO switches, this switch exhibits some superior characteristics, including low switching voltage, compact device size and small wavelength dependency.     

Non-blocking four-port optical router based on thermo- optic silicon microrings

By using silicon-on-insulator(SOI) platform, 12 channel waveguides, and four parallel-coupling one-microring resonator routing elements, a non-blocking four-port optical router is proposed. Structure design and optimization are performed on the routing elements at 1 550 nm. At drop state with a power consumption of 0 m W, the insertion loss of the drop port is less than 1.12 d B, and the crosstalk between the two output ports is less than-28 d B; at through state with a power consumption of 22 m W, the insertion loss of the through port is less than 0.45 d B, and the crosstalk between the two output ports is below-21 d B. Routing topology and function are demonstrated for the four-port optical router. The router can work at nine non-blocking routing states using the thermo-optic(TO) effect of silicon for tuning the resonance of each switching element. Detailed characterizations are presented, including output spectrum, insertion loss, and crosstalk. According to the analysis on all the data links of the router, the insertion loss is within the range of 0.13—3.36 d B, and the crosstalk is less than-19.46 d B. The router can meet the need of large-scale optical network-on-chip(ONo C).     

一种中红外差分甲烷检测仪的研制

根据甲烷(CH₄)分子在中红外波段的吸收特 性并利用宽光谱红外热辐射光源(IR55), 研制了一种基于中红外吸收光谱技术的双通道差分CH₄检测仪。通 过对双通道探测器(3.31 μm和3.90μm)输 出的两路信号进行差分处理,有效抑制了系 统噪声。给出了系统的检测原理和结构,表征了光源和探测器的光学特性。为了提高聚光效 率并增大光程,设计制作了球面反射镜开放气室,其半径约20cm。 配备了16种不同浓 度的CH₄气体样品,开展了气体标定实验,得到了气体浓度 与双通道信号幅值电压的关 系表 达式。 误差实验结果显示, 对16种气体样品的检测误差小于12.4%。 对体积分数为 5×10－4的CH₄气体样品开展的长达10h的浓度测量实验 表明,检测结果的相对波动范围 为±10%。对测得的实验结果进行数理统计,其标准差为2.06×10－5,进而得到该检测仪的检测下限约为6.18×10－5。