牛顿环实验非等精度分析的讨论

牛顿环实验非等精度分析的讨论张希纯（上海机械学院２０００９３）牛顿环实验的非等精度测量问题已作了许多有益的讨论（１）（２）．文［１］中提出测量牛顿环凸透镜半径的误差主要来源于对准条纹时的对准误差．文［２］用标准差传递的“方和根”法得到了误差公式是的函...     

Multiple bottle beams based on metasurface optical field modulation and their capture of multiple atoms

Compared to conventional devices, metasurfaces offer the advantages of being lightweight, with planarization and tuning flexibility. This provides a new way to integrate and miniaturize optical systems. In this paper, a metasurface capable of generating multiple bottle beams was designed. Based on the Pancharatnam-Berry (P-B) phase principle, the metasurface lens can accurately control the wavefront by adjusting the aspect ratio of the titanium dioxide nanopillars and the rotation angle. When irradiated by left-handed circularly polarized light with a wavelength of 632.8 nm, the optical system can produce multiple micron bottle beams. Taking two bottle beams as examples, the longitudinal full widths at half-maximum of the optical tweezers can reach 0.85 μ and 1.12 μ, respectively, and the transverse full widths at half-maximum can reach 0.46 μ and 0.6 μ. Also, the number of generated bottle beams can be varied by controlling the size of the annular obstacle. By changing the x-component of the unit rotation angle, the metasurface can also change the shape of the bottle beam — the beam cross-section can be changed from circular to elliptical. This paper also analyzes the trapping of ytterbium atoms by the multi bottle beam acting as optical tweezers. It is found that the multi bottle beam can cool and trap multiple ytterbium atoms.     

被测量实际值的准确度条件

被测量实际值的准确度条件张希纯（华东工业大学）实际值，按国家技术规范ＪＪＧ１００１—９１给出的定义，是满足规定准确度条件用来代替真值的量值．在物理实验教材中这一名词用得很少，常用公认值、近真值、准确值等代替．在评价测量结果时，常将测量最终结果和实际值...