For real-time monitoring of oxidation or other semiconductor procedures, the exhibited methodology presents remarkable adaptability and can be quickly implemented, provided real-time, precise spatio-spectral (reflectance) mapping is available.
Energy-resolving detectors, pixelated in nature, facilitate the acquisition of X-ray diffraction (XRD) signals via a hybrid energy- and angle-dispersive technique, potentially ushering in the era of novel benchtop XRD imaging or computed tomography (XRDCT) systems, capitalizing on readily available polychromatic X-ray sources. In this investigation, the HEXITEC (High Energy X-ray Imaging Technology), a commercially available pixelated cadmium telluride (CdTe) detector, was applied to exemplify an XRDCT system. Researchers developed and compared a novel fly-scan technique with the established step-scan technique, resulting in a 42% reduction in total scan time and improved spatial resolution, material contrast, and material classification accuracy.
A technique employing femtosecond two-photon excitation was developed for visualizing the interference-free fluorescence of hydrogen and oxygen atoms concurrently in turbulent flames. The single-shot, simultaneous imaging of these radicals in non-stationary flames is a pioneering accomplishment of this work. An investigation into the fluorescence signal, revealing the spatial distribution of hydrogen and oxygen radicals within premixed methane/oxygen flames, was conducted across equivalence ratios from 0.8 to 1.3. Single-shot detection limits are indicated by the quantification of images through calibration measurements, roughly a few percent. Profiles from flame simulations exhibited corresponding characteristics when compared to experimental profiles.
Holography's capacity to reconstruct both the intensity and phase information underlies its application in microscopic imaging, optical security, and data storage. As an independent degree of freedom, the azimuthal Laguerre-Gaussian (LG) mode index, or orbital angular momentum (OAM), has been implemented in holography technologies for high-security encryption. Despite its potential, the radial index (RI) of LG mode has not yet been employed in holographic data encoding. We present and demonstrate RI holography, achieved by utilizing potent RI selectivity in the spatial-frequency domain. DMARDs (biologic) In addition, a theoretical and experimental LG holography process is demonstrated with (RI, OAM) values varying from (1, -15) to (7, 15). This leads to a high-security 26-bit LG-multiplexing hologram for optical encryption. A high-capacity holographic information system can be constructed, leveraging the principles of LG holography. Our experiments successfully implemented LG-multiplexing holography, featuring 217 independent LG channels. This surpasses the current limitations of OAM holography.
We investigate the consequences of intra-wafer systematic spatial variation, pattern density disparities, and line edge roughness for splitter-tree-based integrated optical phased arrays. synbiotic supplement These variations in the array dimension have a considerable effect on the beam profile being emitted. We investigate architectural parameters for their influence, and the analysis aligns remarkably with the empirical results.
We describe the engineering and fabrication of a polarization-keeping fiber designed for fiber optic THz communication. Four bridges hold a subwavelength square core, centrally positioned within a hexagonal over-cladding tube, characterized by its fiber. With the aim of achieving low transmission losses, the fiber is engineered to exhibit high birefringence, extreme flexibility, and near-zero dispersion at the carrier frequency of 128 GHz. An infinity 3D printing technique is employed for the continuous creation of a 5-meter-long polypropylene fiber, having a diameter of 68 mm. Post-fabrication annealing further reduces fiber transmission losses by as much as 44dB/m. Cutback loss measurements taken with 3-meter annealed optical fibers display power attenuation values of 65-11 dB/m and 69-135 dB/m in the 110-150 GHz band, affecting the orthogonally polarized modes. Within a 16-meter fiber optic link operating at 128 GHz, data rates of 1 to 6 Gbps are achieved with bit error rates between 10⁻¹¹ and 10⁻⁵. The demonstration of 145dB and 127dB average polarization crosstalk values for orthogonal polarizations, in 16-2 meter fiber lengths, affirms the fiber's polarization-maintaining property across lengths of 1-2 meters. Lastly, terahertz imaging of the fiber's near field provided evidence of significant modal confinement for the two orthogonal modes, deeply located within the suspended core region of the hexagonal over-cladding. We believe this study exhibits the strong potential of the 3D infinity printing technique augmented by post-fabrication annealing to continually produce high-performance fibers of complex geometries, crucial for rigorous applications in THz communication.
Gas jets' below-threshold harmonic generation serves as a promising approach toward realizing optical frequency combs in the vacuum ultra-violet (VUV) spectrum. Probing the nuclear isomeric transition in the Thorium-229 isotope can be effectively achieved utilizing the 150nm wavelength spectrum. High-power, high-repetition-rate ytterbium lasers, readily available, enable the generation of VUV frequency combs through the process of below-threshold harmonic generation, such as the seventh harmonic of 1030nm light. A critical aspect of developing suitable VUV light sources hinges on knowledge of the achievable efficiencies of the harmonic generation process. Within this study, we quantify the overall output pulse energies and conversion efficiencies of sub-threshold harmonics in gas jets, employing a phase-mismatched generation strategy with Argon and Krypton as nonlinear media. A 220-femtosecond, 1030-nanometer light source produced a maximal conversion efficiency of 1.11 x 10⁻⁵ for the 7th harmonic (147 nm) and 7.81 x 10⁻⁴ for the 5th harmonic (206 nm). We also characterize the third harmonic component of a 178 femtosecond, 515 nanometer light source, showcasing a peak efficiency of 0.3%.
To realize a fault-tolerant universal quantum computer, continuous-variable quantum information processing requires non-Gaussian states possessing negative Wigner function values. Experimentally, while several non-Gaussian states have been created, none were produced using ultrashort optical wave packets, crucial for high-speed quantum computation, in the telecommunications wavelength band where well-established optical communication technology exists. In the 154532 nm telecommunications wavelength band, we present the creation of non-Gaussian states on wave packets lasting only 8 picoseconds. The method used for this involved photon subtraction, limited to a maximum of three photons. Using a low-loss, quasi-single spatial mode waveguide optical parametric amplifier, a superconducting transition edge sensor, and a phase-locked pulsed homodyne measurement system, we scrutinized the Wigner function, discovering negative values without any loss correction up to three-photon subtraction. The ramifications of these results extend to the creation of more complex non-Gaussian states, thereby significantly impacting the development of high-speed optical quantum computing.
A scheme to realize quantum nonreciprocity is described, which hinges on manipulating the probabilistic attributes of photons within a compound device. This device comprises a double-cavity optomechanical system, a spinning resonator, and nonreciprocal coupling. The spinning apparatus's response to unidirectional driving, rather than symmetrical driving with equivalent force, produces the photon blockade effect. Analytic solutions for the two sets of optimal nonreciprocal coupling strengths required for a perfect nonreciprocal photon blockade are obtained under different optical detunings. The solutions stem from the destructive quantum interference between various paths, and match the results of numerical simulations. Besides, the photon blockade manifests profoundly distinct characteristics when subjected to alterations in nonreciprocal coupling, and a complete nonreciprocal photon blockade can be attained even with weak nonlinear and linear couplings, rendering conventional perception obsolete.
We present, for the first time, a strain-controlled all polarization-maintaining (PM) fiber Lyot filter, a device constructed using a piezoelectric lead zirconate titanate (PZT) fiber stretcher. Within an all-PM mode-locked fiber laser, this filter is implemented as a novel wavelength-tuning mechanism enabling rapid wavelength sweeping. A linear tuning range from 1540 nm to 1567 nm is attainable for the central wavelength of the output laser. DW71177 Strain sensitivity in the proposed all-PM fiber Lyot filter reaches 0.0052 nm/ , representing a 43-fold enhancement over strain-controlled filters like fiber Bragg grating filters, whose sensitivity is limited to 0.00012 nm/ . Wavelength sweeping at rates up to 500 Hz and wavelength tuning speeds of up to 13000 nm/s are verified. These parameters significantly exceed those possible with traditional sub-picosecond mode-locked lasers using mechanical tuning, enabling a speed improvement of hundreds. Swift and highly repeatable wavelength tuning is a hallmark of this all-PM fiber mode-locked laser, making it a prospective source for applications demanding rapid wavelength adjustments, including coherent Raman microscopy.
Employing the melt-quenching technique, tellurite glasses (TeO2-ZnO-La2O3) incorporating Tm3+/Ho3+ were prepared, and their luminescence spectra within the 20m band were examined. Tellurite glass, co-doped with 10 mole percent Tm2O3 and 0.085 mole percent Ho2O3, exhibited a fairly flat, broad luminescence band between 1600 and 2200 nm when excited by an 808 nm laser diode. This emission is due to spectral overlapping of the 183 nm band of Tm³⁺ ions and the 20 nm band of Ho³⁺ ions. After the introduction of 01mol% CeO2 and 75mol% WO3, a remarkable 103% enhancement was observed. The primary cause of this enhancement is the cross-relaxation between Tm3+ and Ce3+ ions, accompanied by the improved energy transfer from the Tm3+ 3F4 level to the Ho3+ 5I7 level, a consequence of the rise in phonon energy levels.