688 to 0.690 eV. An absorption ratio of 1.81 under -2 V was achieved at 2 μm, which shows early promise for effective optical modulation. The high frequency response was calculated theoretically, and the predicted 3-dB bandwidth for the photodiode with a mesa diameter of 30 μm could reach 12 GHz at -2 V.A sub-100 fs all-fiber broadband optical frequency comb seeded from a 12.5 GHz electro-optic modulated pulse is presented. Combining pulse reshaping, nonlinear mixing with dispersion compensation processes, a frequency comb with the main pulse width of 86 fs was achieved. The frequency comb has a 6 dB spectral bandwidth spanning over 150 nm which corresponding to more than 1500 comb tones. The measured average power of the broadband comb is over 550 mW, and the calculated average power of each comb line is roughly -4 dBm. To illustrate the whole spectral broadening process, a numerical investigation was also brought out, showing a very good match with the experiments. With a delayed self-heterodyne interferometer, the evolutions of the seed comb linewidths and the broadened comb linewidths were measured revealing the same parabolic trend. Specifically, the linewidths of the 20 seed comb lines are less than 10 kHz, while the linewidths of the 400 broadened comb lines are less than 1 MHz. The results also indicate that the nonlinear mixing led to an accumulation of the phase noise with respect to the comb line number, indicating that a low phase noise RF source or phase locking technique is essential to produce ultra-low phase noise broadband electro-optic combs.Since the domain wall photovoltaic effect (DW-PVE) is reported in BiFeO3 film, the investigations on photovoltaic properties in ferroelectrics have appealed more and more attention. In this work, we employed two Fe doped KTa1-xNbxO3 (FeKTN) single crystals in tetragonal phase and orthorhombic phase, respectively, possessing similar net polarization along [001]C direction, to quantize the contribution on photovoltaic properties from bulk photovoltaic effect (BPVE) and DW-PVE in FeKTN. The results show that there are significant enhancements of open-circuit voltages (VOC = -6.0 V, increases over 440%) and short-circuit current density (JSC = 18.5 nA cm-2, increases over 1580%) in orthorhombic FeKTN with engineer-domain structure after poled, corresponding to 14.2 mV and 2.2 mV for the single domain wall and bulk region under illumination of 405 nm light (100 mW). It reveals that DW-PVE plays a major role in KTN-based ferroelectrics, indicating an orthorhombic FeKTN single crystal is one of the potential photovoltaic materials.We present a method of post-deposition tuning of the optical properties of thin film dielectric filters and mirrors containing chalcogenide glass (ChG) layers by thermally adjusting their refractive index. A common challenge associated with the use of ChG films in practical applications is that they suffer from slight run-to-run variations in optical properties resulting from hard-to-control changes in source material and deposition conditions. These variations lead to inconsistencies in optical constants, making the fabrication of devices with prescribed optical properties challenging. In this paper, we present new work that takes advantage of the large variation of a ChG films' refractive index as a function of annealing. We have carried out extensive characterization of the thermal index tuning and thickness change of arsenic selenide (As2Se3) ChG thin films and observed refractive index changes larger than 0.1 in some cases. We show results for refractive index as a function of annealing time and temperature and propose a model to describe this behavior based on bond rearrangement. We apply thermal refractive index tuning to permanently shift the resonance of a Fabry-Perot filter and the cutoff wavelength of a Bragg reflector. The Bragg reflector, consisting of alternating As2Se3 and CaF2 layers, exhibits high reflectance across a ∼550 nm band with only five layers. Modeling results are compared with spectroscopic measurements, demonstrating good agreement.We theoretically investigate the optical memory in a nanofiber system via electromagnetically induced transparency (EIT) in a nonlinear region. Because of the tight transverse confinement, the light-atom interaction is significantly enhanced and thus, the EIT effect is enhanced. The inhomogeneous mode field distribution contributes spatially to the EIT dispersion. We develop a systematic analysis method to study the nonlinearity of the system and prove that the optical soliton is available in the system and can be stored and retrieved with high efficiency and stability. We also study a strategy to optimize the soliton optical memory. The results obtained in this study are promising for practical applications of all-optical information processing.Portable sensors with a sufficiently high sensitivity in detecting small rotational motions have attracted significant attention in the field of rotational seismology. In this study, we propose and demonstrate a dual-polarization fiber optic gyroscope (IFOG) with a portable-sized fiber coil. Excess relative intensity noise (RIN) is effectively compensated for owing to the opposite parities and strong correlation of the two orthogonal polarized light, whereas other noises including coherent phase noise and thermal phase noise have also been handled well. In a test on detecting the rotation rate of the Earth, an enhanced sensitivity of 20nrad/s/Hz over a frequency range of 0.01 Hz to 30 Hz was demonstrated using the proposed design with an enclosed area of only 68 m2.One of the important features of tabletop 3D displays is the annular viewing area above the display system. In this paper, we propose an annular sector elemental image array (ASEIA) generation method for the tabletop integral imaging 3D display to form the annular viewing zone with smooth motion parallax.  https://www.selleckchem.com/products/a2ti-2.html  The effective pixels of the elemental images are distributed as annular sector, and they are mapped from the perspective images captured by the ring-shaped camera array. Correspondingly, the viewing sub-zones can be formed with an annular sector configuration and can be seamlessly stitched by using the time division scheme. Compared with the previous approach with rectangular elemental image array (EIA) distribution, the number of viewing sub-zones is decreased from 360 to 10 for the same effect of smooth motion parallax. Meanwhile, rendering efficiency is improved. The experimental results show that the proposed method is feasible to produce 360-degree continuous viewpoints in an annular viewing zone.