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Erratum: Peng, T.-P. Comprehension Human-Nature Cable connections By means of Scenery Socialization. Int. T. Environ. Res. Public Well being 2020, 17, 7593.
Anxiolytic effect of chronic utilization of extra magnesium mineral chloride inside rat.
59 and -17.74 dBm, respectively, indicating that the 2.04 µm data transmission system is more reliable under an extremely dense smoke condition.We experimentally investigate the semiconductor-to-metal transition (SMT) in vanadium dioxide thin films using an infrared thermographic technique. During the semiconductor to metal phase change process, VO2 optical properties dynamically change and infrared emission undergoes a hysteresis loop due to differences between heating and cooling stages. link= ABT-199 price The shape of the hysteresis loop was accurately monitored under different dynamic heating/cooling rates. In order to quantify and understand the effects of different rates, we used a numerical modelling approach in which a VO2 thin layer was modeled as metamaterial. The main experimental findings are interpreted assuming that both the rate of formation and shape of metallic inclusions are tuned with the heating/cooling rate. The structural transition from monoclinic to tetragonal phases is the main mechanism for controlling the global properties of the phase transition. ABT-199 price However, our experimental results reveal that the dynamics of the heating/cooling process can become a useful parameter for further tuning options and lays out a macroscopic optical sensing scheme for the microscopic phase change dynamics of VO2. Our study sheds light on phase-transition dynamics and their effect on the infrared emission spectra of VO2 thin films, therefore enabling the heating/cooling rate to be an additional parameter to control infrared emission characteristics of thermal emitters. link2 The hysteresis loop represents the phase coexistence region, thus being of fundamental importance for several applications, such as the operation of radiative thermal logic elements based on phase transition materials. For such applications, the phase transition region is shifted for heating and cooling processes. We also show that, depending on the way the phase change elements are heated, the temperature operation range will be slightly modified.We report on performance studies of high-average-power single-pass picosecond optical parametric generation (OPG) and amplification (OPA) tunable near 2 µm in MgOPPLN pumped by an Yb-fiber laser at 1.064 µm and 80 MHz pulse repetition rate. The simple setup based on two identical crystals, and without the need for an intermediate delay line for synchronization, delivers up to 6.3 W of average power at an overall conversion efficiency of ∼50% and is tunable across 1902-2415 nm. We present systematic characterization of OPG and OPA stages to compare their performance and investigate the effect of parametric generation in the high-gain limit, enabling high output power and full-width-half-maximum (FWHM) spectral bandwidths as large as 189 nm. The OPG-OPA output exhibits excellent passive power stability better than 0.3% rms and central wavelength stability better than 0.03% rms over 1 hour, in high spatial beam quality with M2 less then 2. The OPG output pulses have duration of 5.2 ps with a FWHM spectral bandwidth of 117 nm at 2123 nm, resulting in a time-bandwidth product of ΔτΔν∼40, indicating ∼4 times temporal compression compared to the input pump pulses. Theoretical simulations confirm the effect of pump beam divergence on the observed shift in wavelength tuning with respect to temperature, while the exponential gain in the parametric process is identified as playing a key role in the resulting pulse compression.We demonstrate the enhancement of the resolution of a fiber optical sensor using all-optical signal processing. By sweeping the frequency of a tunable laser across a fiber Bragg grating, a signal corresponding to the reflection spectrum of the FBG is generated. If another laser with fixed power and frequency is launched into a highly nonlinear fiber along with the FBG-shaped signal, the Kerr effect gives rise to a number of frequency sidebands, where the power in each of the sidebands is proportional an integer exponent of the signal and pump powers. By filtering out particular sidebands, this potentiation effect reduces the width of the FBG-shaped signal, making shifts in its central wavelength easier to distinguish. We report a maximum resolution enhancement factor of 3.35 obtained by extracting the n = -4 order sideband, and apply resolution enhancement to improve the resolution of an FBG based temperature sensor. The method described in this paper can be applied to existing fiber based sensors and optical systems to enhance their resolution.Multi-frequency temporal phase unwrapping (TPU) has been extensively used in phase-shifting profilometry (PSP) for the high-accuracy measurement of objects with surface discontinuities and isolated objects. However, a large number of fringe patterns are commonly required. link3 To reduce the number of required patterns, a new hybrid multi-frequency composite-pattern TPU method was developed using fewer patterns than conventional TPU. The new method combines a unit-frequency ramp pattern with three low-frequency phase-shifted fringe patterns to form three composite patterns. These composite patterns are used together with three high-frequency phase-shifted fringe patterns to generate a high-accuracy phase map. The optimal high frequency to achieve high measurement accuracy and reliable phase unwrapping is determined by analyzing the effect of temporal intensity noise on phase error. Experimental results demonstrated that new grayscale hybrid and color hybrid multi-frequency composite-pattern TPU methods can achieve a high-accuracy measurement using only six and three images, respectively.Hexagonal boron nitride (h-BN) as a natural mid-infrared (mid-IR) hyperbolic material which supports a strong excitation of phonon polariton (PhP) has enabled a new class of photonic devices with unprecedented functionalities. The hyperbolic property of h-BN has not only brought in new physical insights but also spurred potential applications. However, most of the current h-BN devices are designed repying on near-field excitation and manipulation of PhP. For fully realizing the potentials of h-BN, research on far-field controllable excitation and control of PhP is important for future integrated photonic devices. In this work, we exploit the designs of controllable far-field excitation of PhP in nanostructure-patterned h-BN thin film for deep subwavelength focusing (FWHM∼λ0/14.9) and interference patterns of 1D (FWHM∼λ0/52) and 2D standing waves (FWHM∼λ0/36.8) which find great potential for super-resolution imaging beyond diffraction limit. These polaritonic patterns could be easily tuned remotely by manipulating the polarization and phase of incident laser. This approach provides a novel platform for practical IR nanophotonic devices and potential applications in mid-IR bio-imaging and sensing.The Fresnel-zone-aperture lensless camera using a fringe-scanning technique allows non-iterative well-conditioned image reconstruction; however, the spatial resolution is limited by the mathematical reconstruction model that ignores diffraction. To solve this resolution problem, we propose a novel image-reconstruction algorithm using the wave-optics-based design of the deconvolution filter and color-channel image synthesis. We verify a two-fold improvement of the effective angular resolution by conducting numerical simulations and optical experiments with a prototype.Two-photon absorption spectra are difficult to observe using direct absorption spectroscopy especially in the near-infrared region. Cavity ring-down spectroscopy is a promising absorption spectroscopy technique which has been widely applied to linear and saturated single-photon absorption spectra. In the present study, we report the observation of a possible two-photon absorption in the near-infrared using cavity ring-down spectroscopy, namely a two-photon resonance of methane. Using an optical frequency comb, the single-photon wavenumber of the double-quantum transition has been determined to be 182 207 682.645 MHz with a standard deviation of 75 kHz.There are several applications for enhancement cavities where a beam of large size (several millimeters) resonates, in particular in atomic physics. However, reaching large beam waists in a compact geometry (less than a meter long) typically brings the resonator close to the degeneracy limit. Here we experimentally study a degenerate optical cavity, 44-cm long and consisting of two flat mirrors placed in the focal planes of a lens, in a regime of intermediate finesse (∼150). We study the impact of the longitudinal misalignement on the optical gain, for different input beam waists up to 5.6 mm, and find data consistent with the prediction of a model based on ABCD propagation of Gaussian beams. ABT-199 price We reach an optical gain of 26 for a waist of 1.4 mm, which can have an impact on several applications, in particular atom interferometry. We numerically investigate the optical gain reduction for large beam waists using the angular spectrum method to consider the effects of optical aberrations, which play an important role in such a degenerate cavity. Our calculations quantitatively reproduce the experimental data and will provide a key tool for designing enhancement cavities close to the degeneracy limit. As an illustration, we discuss the application of this resonator geometry to the enhancement of laser beams with top-hat intensity profiles.The success of ever-thinner photovoltaics relies on the introduction of light management strategies to enhance the absorption of incident illumination. Tailoring these strategies to maximise the absorption of light requires optimising the complex interplay between multiple design parameters. link2 We study this interplay with a transfer matrix method and rigorous coupled-wave analysis, within the context of waveguide modes in an ultra-thin (80 nm) GaAs solar cell. Based on this study, we develop a framework for light management optimisation which is guided by the underlying optical phenomena that determine the most favourable design parameters. In contrast to other optimisation approaches which exhaustively simulate multiple parameter combinations looking for the highest integrated absorption, our framework reduces the parameter space for optimisation, furthers our fundamental understanding of light management and is applicable to multiple length-scales and device architectures. We demonstrate the power of our framework by using it to compare the light trapping performance of photonic crystal gratings to that of engineered quasi-random structures, finding that photonic crystal gratings offer a superior performance in our device of interest.We report on the nonlinear characterizations of the titanium dioxide micro-ring resonators (TiO2 MRRs). By utilizing optimized fabrication processes, high quality factors (Q∼1.4 × 105) doubling that of the previous work are achieved here for TiO2 MRRs with high-confinement TiO2 waveguides. The four-wave mixing (FWM) experiment results with low and high signal power demonstrate that, the fabricated TiO2 MRRs can perform broadband (∼40 nm) wavelength conversion and cascaded FWMs. link3 These achievements pave the way for key nonlinear photonic applications with TiO2 waveguides and provide an efficient platform for various integrated photonic devices.