Brixgilliam6115

We present a novel concept for a Thomson scattering diagnostic, based on a high-speed fiber optic spectrometer. The high-speed fiber optic spectrometer presented here translates a spectral measurement from the frequency domain into the time domain, thus requiring the use of only a single photodetector for spectral acquisition. The high temporal precision offered by the instrument gives rise to a number of advantages over traditional spectrometers, such as nearly background-free measurements and multiple uses of the same injected beam. Multiple uses of the same beam would enable greatly increased measurement rates, in the range of 10-100 MHz. The spectral range and resolution of the fiber spectrometer can be easily tailored to be optimized for the light source and experimental conditions by selecting different lengths of fiber, thus allowing for the proposed technique to exhibit high dynamic range when measuring many points simultaneously. Finally, due to the temporal separation of the background from the signal, these improvements are possible without the need for increased average input laser power.We describe a ball lens assembly, which functions as a broadly tunable bandpass filter and polarizer with imaging capabilities. The physical basis is resonant tunneling of light through an air gap between two half-ball lenses symmetrically coated by few-layer (Si/SiO2 or Ta2O5/SiO2) admittance matching stacks. Tuning is achieved by simultaneous adjustments of the incident angle and the air gap thickness. Individual filters with operational ranges spanning visible (∼400-700nm) and near-infrared (∼1000-1800nm) wavelengths were assembled using 10 mm diameter lenses. We show that these filters, configured as a stand-alone scanning spectrometer, can provide a resolving power ∼100 and f-number ∼2.5 for a fiber-compatible input aperture less then 15µm in diameter. this website We also demonstrate that, with supplementary optics, the tunable ball filter might be used to implement a compact hyperspectral imaging system.We present the generation of 41 noise-like pulse (NLP) envelopes with complex shapes using a passively mode-locked, erbium-doped figure-eight fiber laser (EDFEFL). The tuning of each of the complex forms was carried out by varying the polarization state within the laser cavity, using a quarter-wave retarder (QWR2) inside a nonlinear optical loop mirror (NOLM), which is part of the EDFEFL. The position of the retarder plate was identified and recorded for each of the complex shapes. The temporal and spectral characterization was done using the position of the WQR2 wave plate as an independent variable. We present a single-shot analysis of the dynamics for the temporal amplitude, the full width at half-maximum (FWHM), and the root-mean-square (RMS) width for each of the 360 cycles measured for the 41 complex envelopes. We also perform an analysis for the case in which the pulse is completely divided into subpackets. We analyze the corresponding spectral profile for each of the complex forms generated. Finally, we evaluate the performance of the NOLM theoretical model with our experimental results. The wavelength of the NLPs is 1560 nm; the period of the cavity fiber laser is 1.1 ms; and the temporal FWHM is within the range of nanoseconds.We analyze non-diffracting fields (NDFs) with Fourier spectra that are phase-only azimuthally modulated. In this context, we identify a weak interference regime of the different Bessel beams that compose each NDF, which allows the use of a simple method to control several features of this field. The approach is illustrated considering periodic sinusoidal and binary azimuth phases. For generation of the NDFs, we employ an experimental setup that operates using a sequential double phase modulation in a spatial light modulator.Ce3+ doped M3Al5O12 (MAG, M=Lu, Y) glass ceramics (GCs) have been proved to be shapeable phosphors for white lighting driven by a 453 nm laser. Quantitative characterization reflects that the net emission powers of 4 wt% LuAG-doped GC and 4 wt% YAG-doped GC are 59.99 mW and 66.22 mW at the pump power of 117.63 mW, and the quantum yields reach up to 71.1% and 78.0%, respectively. Miniaturization of devices can be achieved for LuAG/YAG-GCs by optimizing sample size and phosphor concentration with maintaining fluorescence intensity of the samples. Presupposed color coordinate trace reveals that the high-brightness white fluorescence can be realized when the appropriate intensity ratio is determined between residual laser and sample emission. The tunable white fluorescence and the efficient radiation releasing illustrate that LuAG/YAG-GCs are potential candidates for application in solid-state laser illumination.We systematically studied the effect of p-electrode patterns on the optical properties and -3dB bandwidth of micro-size LEDs. The current spreading distribution can be effectively improved via adjusting the number and shape of the p-electrode branch, thus increasing the injection saturation current density and decreasing the series resistance. Compared with the micro-size LED using a disk p-electrode, the saturation light output power and -3dB bandwidth of the micro-size LED using a six-branches spiral p-electrode increase by 39.48% and 76.61%, respectively. Such a p-electrode pattern is a promising solution for micro-size LED applications in both illumination and visible light communication systems.This paper describes a novel, to the best of our knowledge, approach to build ultrastable interferometers using commercial mirror mounts anchored in an ultralow expansion (ULE) base. These components will play a critical role in any light particle search (ALPS) and will also be included in ground testing equipment for the upcoming laser interferometer space antenna (LISA) mission. Contrary to the standard ultrastable designs where mirrors are bonded to the spacers, ruling out any later modifications and alignments, our design remains flexible and allows the alignment of optical components at all stages to be optimized and changed. Here we present the dimensional stability and angular stability of two commercial mirror mounts characterized in a cavity setup. The long-term length change in the cavity did not exceed 30 nm and the relative angular stability was within 2 µrad, which meet the requirements for ALPS. We were also able to demonstrate 1pm/Hz length noise stability, which is a critical requirement for various subsystems in LISA.