Notes

Garden practices in B razil natural farms as well as microbiological qualities regarding examples obtained over the creation archipelago.
Recently, laser-driven resonant fiber-optic sensors (FOSs) have been reported to reach the ultimate resolution limit, set by the thermal noise in fiber. However, they are still far away from commercialization because of their dependence on expensive and ultra-narrow-linewidth lasers. In this Letter, a white-light-driven resonant FOS is proposed for the first time, to the best of our knowledge. By using the white-light multi-beam interferometry, the resonant peaks of a fiber Fabry-Perot interferometer sensor are obtained, and the resonance drifts are tracked for sensor readout by using the Pound-Drever-Hall technique. The proposed FOS is adopted for strain measurement, and the achieved strain resolution (0.9pε/√Hz at 100 Hz) is comparable with that of laser-driven FOSs.Photon counting lidar signals generally require smoothing to suppress random noise. While the process of reducing the resolution of the profile reduces random errors, it can also create systematic errors due to the smearing of high gradient signals. The balance between random and systematic errors is generally scene dependent and difficult to find, because errors caused by blurring are generally not analytically quantified. In this work, we introduce the use of Poisson thinning, which allows optimal selection of filter parameters for a particular scene based on quantitative evaluation criteria. Implementation of the optimization step is relatively simple and computationally inexpensive for most photon counting lidar processing.This Letter proposes and demonstrates a novel, miniature fiber-tip temperature sensor with a tapered hollow capillary tube (HCT) filled with glycerin and dye-doped cholesteric liquid crystal (CLC). The function of glycerin is to provide a surface anchoring force to control the uniform orientation of CLC molecules, so that the CLC in the tapered HCT can be considered as a mirrorless photonic bandgap (PBG) microcavity. An unambiguously identifiable PBG mode single peak appears in the emission spectra of the sensor. The CLC-based fiber-tip temperature sensor has a temperature sensitivity of -9.167nm/∘C, and the figure of merit can reach 67.4∘C-1. This sensor offers key features and advantages, including compactness, unambiguous identifiability, and biocompatibility, which can satisfy requirements of temperature measurement in various temperature sensing application fields and has great potential for biochemical detection at cell level. In addition, the CLC was integrated into the optical fiber terminal, and the PBG mode is excited, collected and transmitted by the multimode fiber coupler, which is reported for the first time, to the best of our knowledge.We report a new method for excitation of magnetic resonance in an optically aligned atomic ensemble. It employs a comb-like rf field acting on the end sublevels of the Fg=1 state separated by the doubled Zeeman frequency. This approach provides a resonance without substructures associated with the quadratic Zeeman shift. A theoretical explanation of the effect is given in terms of the two-quantum transition |F g =1,m F g =-1⟩⇆|F g =1,m F g =1⟩ and is corroborated by an experiment with 87Rb atoms. Possible advantages of the approach and its range of applicability are discussed.The filtering of overlapping spectral regions may be used to increase the observer's gamut in some cases. Therefore, metasurface-based contact lenses (M-CL) may improve the color coding for specific stimuli and deuteranomaly conditions. Here, we address the concerns made by Huertas et al. [Opt. Lett.45, 5117 (2020)OPLEDP0146-959210.1364/OL.394717], regarding the color perception improvement obtained by color filters, in general, and specifically by our M-CL, in case of deuteranomaly.Recently Karepov and Ellenbogen [Opt. Lett.45, 1379 (2020)OPLEDP0146-959210.1364/OL.384970] claimed that a new metasurface-based contact lens is able to correct deuteranomaly. Unfortunately, their results are not supported by psychophysical experiments, and some key assumptions in their simulations were misinterpreted. All of this has led to wrong conclusions providing false expectations to the color vision deficiency community.We demonstrate the feasibility of resetting and reusing dosimeters exploiting the measurement of the infrared radiation-induced attenuation (IR-RIA) in phosphosilicate optical fibers (OFs) to provide point or distributed dose measurements in radiation environments. To bleach the room temperature stable IR-RIA, we used the photobleaching (PB) phenomenon. The PB efficiency was evaluated for different wavelengths in the [400-1100] nm range. The best identified PB resetting condition consists in using a continuous-wave Argon-ion laser at 514 nm. This treatment successfully bleached ∼97% of the IR-RIA at 1550 nm of a 30 m-long P-doped single mode optical fiber X-ray irradiated at a dose of 100 Gy. Successive re-irradiations of the same OF sample, regenerated after each run, confirm that the dosimeter keeps the same calibration curve during the whole process.Perfect vortex beams (PVBs) have intensity distributions independent of their topological charges. We propose an alternative formulation to generate PVBs through Laguerre-Gauss beams (LGBs). Using the connection between Bessel and LGBs, we formulate a modified LGB that mimics the features of a PVB, the perfect LGB (PLGB). The PLGB is closer to the ideal PVB, maintaining a quasi-constant ring radius and width. Furthermore, its number of rings can be augmented with the order of the Laguerre polynomial, showing an outer ring independent of the topological charge. Since the PLGB comprises a paraxial solution, it is closely related to an experimental realization, e.g., using spatial light modulators [Phys. Selleckchem GSK484 Rev. A100, 053847 (2019)PLRAAN1050-294710.1103/PhysRevA.100.053847].Embedding a thin layer of a noble metal between two symmetric media results in the hybridization of the surface plasmons, leading to the existence of a long-range surface plasmon (LRSP). In this Letter, we investigate numerically the coupling of a single dipole, as a probe, to this LRSP. Different de-excitation channels are available such as free space radiation and plasmonic modes in different proportions. In a more realistic approach, with finite layers, guided modes in the dielectric may also be excited. The study of the local density of optical states allows us to separate, identify, and reconstruct the different modes. The critical role of the orientation as well as the position of the dipole leads to an interplay between the LRSP and the guided modes. The coupling efficiency with these modes is evaluated. Besides providing a deep understanding of a LRSP in realistic devices, these results could be used as guidelines for future optoelectronic device designs.
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