Optics (physics.optics)

Abstract: In this paper, first we present a review of experimental data corresponding to phase retardation per reflection of interferential mirrors. Then, we report our new measurements on both commercial and tailor-made mirrors. To be able to measure the phase retardation as a function of the number of layers, additional pairs of layers are deposited on some of the mirrors. The results obtained with this special set of mirrors allow us to fully characterise the waveplate associated with the additional pairs of layers. We finally implemented a computational study whose results are compared with the experimental ones. Thanks to the additional layers, we have achieved reflectivity never measured before at $\lambda=1064$~nm, with an associated finesse of $\mathcal{F}=895~000$.

Abstract: We provide a simple analysis based on ray optics and Dirac notation for one and two-dimensional Cosine beams. We then went on to understand the properties of the Bessel beams. For the first time, we report on a generation of three-dimensional needle structures based on interference of one-dimensional Cosine beams. Straightforward mathematical calculations are used to derive the analytical expressions for Cosine beams. The present method of demonstration of Cosine beams may be utilized to understand other structured modes. The Dirac notation-based interference explanation used here can render new researchers to discover an easy way to understand the wave nature of light in fundamental interferometric experiments as well as in advanced-level experiments such as beam engineering technology, imaging, particle manipulation, light sheet microscopy, and light-matter interaction. We also provide an in-depth analysis of similarities among Cosine, Bessel, and Hermite-Gaussian beams.