Design of low-loss Nb2O5-based grating coupler in scanning differential laser-Doppler integrated probe for cross-sectional velocity distribution measurement
Design of low-loss Nb2O5-based grating coupler in scanning differential laser-Doppler integrated probe for cross-sectional velocity distribution measurement
复制标题
扫描差分激光多普勒一体化探头横截面速度分布测量中低损耗Nb2O5光栅耦合器设计
DOI：
10.1117/1.oe.62.3.037102
复制
发表时间：
2023
影响因子：
1.3
通讯作者：
Nakatsuhara Katsumi
中科院分区：
文献类型：
--
作者：
Maru Koichi;Yamamoto Yoshinobu;Nakatsuhara Katsumi
提出了一种基于Nb2O5/SiO2多层膜的光栅耦合器，用于提高扫描式差分激光-多普勒集成探头的光输入/输出功率效率，用于二维截面速度分布测量。设计了多层Nb2O5/SiO2结构的发射光栅耦合器和接收光栅耦合器。为了证明所设计的多层的效果，模拟了光栅耦合器周围的场分布作为概念的可行性研究。结果表明，在1530~1570 nm波长范围内，采用多层Nb2O5/SiO2膜可以提高光栅耦合器的输入输出功率。通过时域有限差分法和光束传输法的数值模拟，证实了透射光栅耦合器的输入输出功率的增加和聚焦作用。
We present an Nb2O5-based grating coupler that employs multiple Nb2O5/ SiO2layers to improve the optical input/output power efficiency of a scanning differential laser-Doppler integrated probe for two-dimensional cross-sectional velocity distribution measurements. The multiple Nb2O5/ SiO2layers are designed for both the transmitting grating coupler and the receiving grating coupler. To demonstrate the effect of the designed multiple layers, the field distribution around the grating coupler is simulated as a feasibility study of the concept. The results indicated that the input/output power at the grating coupler can be improved using multiple Nb2O5/ SiO2layers over the input/output angle of 0 to 20 deg and the wavelength of 1530 to 1570 nm. The increase of the input/output power and the focusing from the transmitting grating coupler were confirmed by the simulation using the finite-difference time-domain method and beam propagation method.