Author Affiliations
Abstract
1 School of Physics, East China University of Science and Technology, Shanghai 200237, China
2 Shanghai Engineering Research Center of Hierarchical Nanomaterials, Shanghai 200237, China
3 Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai 200237, China
Nitrogen-vacancy (NV) centers in diamond are progressively favored for room-temperature magnetic field measurement. The signal to noise ratio (SNR) optimization for NV diamond magnetometry generally concentrates on signal amplitude enhancement rather than efficient noise processing. Here, we report a compound filter system combining a wavelet denoising method and an adaptive filter for the realization of an efficient weak magnetic measurement with a high SNR. It allows enhanced magnetic field measurement with an average SNR enhancement of 17.80 dB at 50 nT within 500 mHz to 100 Hz and 14.76 dB at 500 mHz within 50 nT to 1100 nT. The introduction of this system in NV diamond magnetometry is aimed to improve signal quality by effectively eliminating the noise and retaining ideal signals.
nitrogen-vacancy center quantum sensing signal processing Chinese Optics Letters
2023, 21(11): 111201
1 华北理工大学药学院，唐山 063210
2 华北理工大学材料科学与工程学院，唐山 063210
3 河北省无机非金属材料重点实验室,唐山 063210
4 唐山市环境功能材料重点实验室,唐山 063210
以八水氧氯化锆(ZrOCl2?8H2O)为原料制备前驱体溶液，采用旋涂工艺制备ZrO2薄膜，并对其进行还原氮化。利用XRD、FE-SEM、UV-Vis-Nir和Raman测试薄膜结构、光学性能及SERS效应。结果表明，还原氮化后薄膜中出现了氮氧化合物，颗粒明显，薄膜厚度约为0.77 μm。薄膜的紫外可见近红外光谱在350~650 nm附近展现出较强的吸收。利用R6G作为探针分子研究了薄膜的SERS效应，结果表明，还原氮化后的氧化锆薄膜拉曼增强效应显著提升，拉曼增强因子为2.479×102。
氧化锆薄膜 还原氮化 表面增强拉曼散射 拉曼增强因子 ZrO2 film reduction and nitridation SERS Raman enhancement factor
三维点云配准是三维重建过程中的重要环节, PCA算法应用于点云配准时无法保留点云局部特征, 影响了配准效果, 故提出一种基于保局PCA的三维点云配准算法。为了保留点云局部特征, 采用保局投影LPP的思想, 通过K近邻准则构造点云的邻接图及其补图; 对邻近点和非邻近点采取不同的处理方式进行特征提取, 通过特征矩阵求得转换参数, 进行坐标归一化完成配准; 为了减少光照噪声影响, 对特征向量矩阵前三个主分量加权后求转换参数。实验结果表明, 改进算法在对局部特征结构明显的点云进行配准时有较好的效果, 改善了对光照噪声的鲁棒性。
点云配准 主成分分析 保局投影 point cloud registration PCA locality preserving projection
