Comprehending the influence of metal patches upon the near-field focusing behavior of patchy particles is critical to the reasoned fabrication of a nanostructured microlens. Our research, encompassing both theoretical and experimental approaches, showcases the ability to focus and tailor light waves with the aid of patchy particles. The application of silver films to dielectric particles can yield light beams exhibiting either a hook-like or an S-shaped profile. Simulation results show that the ability of metal films to act as waveguides and the asymmetry in the geometry of patchy particles are responsible for the formation of S-shaped light beams. As opposed to classical photonic hooks, S-shaped photonic hooks present a more significant effective length and a reduced beam waist in the far-field area. MK-28 order Experimental procedures were implemented to exemplify the formation of both classical and S-shaped photonic hooks, using microspheres with a patchy surface morphology.
Previously, we published a new design for liquid-crystal polarization modulators (LCMs) unaffected by drift, utilizing liquid-crystal variable retarders (LCVRs). This study examines their performance on Stokes and Mueller polarimeters. LCMs, exhibiting polarimetric characteristics akin to LCVRs, can function as temperature-stable replacements for LCVR-based polarimeters. An LCM-based polarization state analyzer (PSA) was developed and its performance was evaluated in comparison to a comparable LCVR-based PSA. Our system's parameters remained unmoved by temperature changes, precisely from 25°C to 50°C. Accurate Stokes and Mueller measurements have prepared the ground for the deployment of polarimeters free from calibration requirements, which are vital for demanding applications.
Recent years have seen augmented/virtual reality (AR/VR) gain traction and investment from both the technological and academic communities, thereby launching a brand new wave of innovations. Prompted by this acceleration, this feature was implemented to address the most recent strides in this growing field of optics and photonics. The 31 published research articles are further contextualized by this introduction, which explores the stories behind the research, submission numbers, reading instructions, details about the authors, and perspectives from the editors.
Wavelength-independent couplers (WICs), based on an asymmetric Mach-Zehnder interferometer (MZI) integrated into a monolithic silicon-photonics platform, are experimentally demonstrated in a commercial 300-mm CMOS foundry. We analyze splitter performance metrics using MZIs formed by circular and third-order Bezier curves. A semi-analytical model is created to enable the accurate calculation of the response of each device, based on its unique geometrical configuration. Experimental characterization and 3D-FDTD simulations have demonstrated the model's efficacy. Uniform performance was observed across diverse wafer locations for differing target split ratios, as demonstrated by the experimental results. The performance of the Bezier bend structure surpasses that of the circular bend configuration, with a lower insertion loss (0.14 dB) and higher consistency across various wafer lots. Precision Lifestyle Medicine Over a span of 100 nanometers in wavelength, the optimal device's splitting ratio's maximum deviation is 0.6%. Moreover, the devices possess a compact footprint, encompassing an area of 36338 square meters.
An intermodal nonlinearity-driven time-frequency evolution model was developed to simulate the spectral and beam quality evolution of high-power near-single-mode continuous-wave fiber lasers (NSM-CWHPFLs) taking into account the combined effects of intermodal and intramodal nonlinearity. Analyzing the impact of fiber laser parameters on intermodal nonlinearities, a method for suppression, involving fiber coiling and optimization of seed mode characteristics, was presented. Experiments to verify the performance were conducted using fiber-based NSM-CWHPFLs with ratios of 20/400, 25/400, and 30/600. The results, in validating the theoretical model, illuminate the physical processes behind nonlinear spectral sidebands, and demonstrate a comprehensive optimization of spectral distortion and mode degradation arising from intermodal nonlinearities.
Chirped factors of the first and second order are applied to an Airyprime beam, enabling the derivation of an analytical expression for its propagation in a free space environment. On a plane other than the original plane, the observed peak light intensity being greater than the intensity on the original plane, is termed interference enhancement, arising from the coherent superposition of chirped Airy-prime and chirped Airy-related modes. The theoretical examination of the influence of the first-order and second-order chirped factors on the interference effect's enhancement is undertaken individually. The first-order chirped factor directly impacts only those transverse coordinates where the maximum light intensity is found. The effectiveness of the interference enhancement in a chirped Airyprime beam, with its negative second-order chirped factor, is definitively stronger than that achievable with a conventional Airyprime beam. Although the interference enhancement effect's strength is improved by the negative second-order chirped factor, this improvement is unfortunately linked to a decrease in the position of the maximum light intensity and the scope of the interference enhancement effect. Experimental investigation into the chirped Airyprime beam reveals its generation method and confirms the impact of both first-order and second-order chirped factors on the enhancement of interference effects. To strengthen the interference enhancement effect, this study implements a method of controlling the second-order chirped factor. Our scheme, offering a more flexible and simpler implementation compared to conventional intensity enhancement strategies, such as lens focusing, stands out. The study's practical impact includes contributions to spatial optical communication and the development of laser processing techniques.
Within this paper, we detail the design and analysis of an all-dielectric metasurface. This structure, arranged periodically on a silicon dioxide substrate, contains a unit cell with a nanocube array. Near-infrared Fano resonances, featuring high Q-factors and significant modulation depths, are potentially generated by utilizing asymmetric parameters to stimulate quasi-bound states within the continuum. Three Fano resonance peaks, stemming from the distributive features of electromagnetism, are simultaneously excited by magnetic dipole and toroidal dipole, respectively. The simulation findings show that the discussed structure can be implemented as a refractive index sensor, displaying a sensitivity of approximately 434 nanometers per refractive index unit, a maximum quality factor of 3327, and a modulation depth of 100%. Following a thorough design phase and experimental testing, the proposed structure demonstrates a peak sensitivity of 227 nanometers per refractive index unit. Under conditions of a zero-degree polarization angle of the incident light, the resonance peak at 118581 nanometers exhibits a modulation depth of nearly 100%. Hence, the suggested metasurface has practical use in optical switching, nonlinear optics, and the development of biological sensors.
The Mandel Q parameter, Q(T), a time-dependent measure, reflects the variation in photon count for a light source, in relation to the integration time. Using Q(T), we characterize the emission of single photons from a quantum emitter embedded within hexagonal boron nitride (hBN). Photon antibunching was indicated by the measured negative Q parameter under pulsed excitation, measured at a 100-nanosecond integration time. Integration time increments lead to a positive Q value and super-Poissonian photon statistics; a three-level emitter Monte Carlo simulation shows the concurrence of this finding with the influence of a metastable shelving state. With a focus on the technological implementation of hBN single-photon sources, we posit that the Q(T) characteristic provides useful information about the constancy of single-photon emission intensity. The commonly used g(2)() function is supplemented by this approach to thoroughly characterize the hBN emitter.
An empirical determination of the dark count rate within a large-format MKID array, mirroring those currently deployed at observatories such as Subaru on Maunakea, is presented. In future experiments, including those designed for dark matter direct detection that require low-count rates and quiet conditions, this work supplies compelling evidence of their utility. The bandpass from 0946-1534 eV (1310-808 nm) exhibits a mean photon count rate of (18470003)x10^-3 photons per pixel per second. The average dark count rate in an MKID, calculated by dividing the bandpass into five equal-energy bins based on the detectors' resolving power, is (626004)x10⁻⁴ photons/pixel/second for the 0946-1063 eV range and (273002)x10⁻⁴ photons/pixel/second for the 1416-1534 eV range. Remediation agent By employing low-noise readout electronics for a single MKID pixel, we show that, when the detector is not exposed to light, the observed events are primarily a mixture of actual photons, possible fluorescence induced by cosmic rays, and phonon events within the array substrate. A single MKID pixel, outfitted with low-noise readout electronics, exhibited a dark count rate of (9309)×10⁻⁴ photons per pixel per second, measured across the 0946-1534 eV bandpass. We also investigated the detector's response when not illuminated, finding that these responses, within the MKID, are distinguishable from photon emissions from known light sources like lasers and are likely attributed to cosmic ray excitations.
The freeform imaging system, a key component in developing an optical system for automotive heads-up displays (HUDs), is representative of typical augmented reality (AR) technology applications. Automated algorithms are urgently needed for the design of automotive HUDs to effectively manage the challenges of multi-configuration, including the variable height of drivers, the movement of eyeballs, correcting distortions from windshields, and considering diverse vehicle structures; however, current research is far from addressing these issues.