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This publisher’s note contains corrections to Opt. Lett.45, 4686 (2020)OPLEDP0146-959210.1364/OL.399623.The strong need in materials and biological science has prompted the development of high-speed quantitative phase imaging. However, for phase retrieval applying digital micromirror devices (DMDs), the accuracy of the retrieved phase will be disturbed by the DMD-induced aberrations. Here, we propose a phase retrieval method based on measuring and correcting errors caused by phase non-uniformity of the device. Using only four binary amplitude masks and corresponding diffraction intensities, the proposed method achieves rapid convergence and high-quality reconstruction. The experiments prove the practical feasibility for general samples and the effective improvement of the retrieved phase accuracy.A compact and broad wavelength range tunable orbital angular momentum (OAM) generator was experimentally demonstrated by cascading two helical photonic crystal fibers (HPCFs) with opposite helicity, i.e., clockwise-twisted + anticlockwise-twisted HPCF. Such an OAM generator exhibited a length of approximately 9 mm and generated a high-quality OAM mode with a wavelength range of 35 nm. Moreover, the wavelength range is expected to be tuned from 17.9-51.3 nm by applying mechanical torsion.In this Letter, we report, to the best of our knowledge, the first demonstration of an in-band pumped gain-switched Dy3+-doped fiber laser operating at 3.24 µm. The monolithic cavity bounded by two fiber Bragg gratings was pumped by a gain-switched Er3+-doped fiber system. It produced stable nanosecond pulses in a single-pulse regime on its entire operating range from 20 kHz to 120 kHz. Envonalkib nmr A record average power of 1.43 W was achieved for a repetition rate of 120 kHz, and a record pulse energy of 19.2 µJ was achieved at 60 kHz. These results represent a significant improvement in Dy3+-doped pulsed fiber laser performances and open the way to applications in the fields of remote sensing and material processing.We experimentally investigate the vector nature of various pulsating solitons in an ultrafast fiber laser with single-wall carbon nanotubes. By virtue of the dispersive Fourier transform technique, the polarization-resolved spectral evolution of pulsating vector solitons is measured in real time. In the case of single-periodic pulsation, pulsating behaviors of the two orthogonal polarization components can be either synchronous or asynchronous. We also observe double-periodic pulsation in the cavity for the first time, to the best of our knowledge. It is shown that the shot-to-shot spectra oscillate with two combined modulation periods involved in this process. Our results would be beneficial for further understanding of the vector dynamics of pulsating solitons in dissipative systems.Orders-of-magnitude increases are desired in the pixel count and density of spatial light modulators (SLMs) for next-gen displays. We present in-plane and simultaneous angular-spatial light modulation by a micro electro mechanical system (MEMS)-based SLM, a digital micromirror device (DMD), to generate gigapixel output by time and angular multiplexing. Pulsed illumination synchronized to the micromirror actuation achieves pixel-implemented and diffraction-based angular modulation, and source multiplexing increases angular selectivity. We demonstrate 1440-perspective image output across a 43.9∘×1.8∘ FOV, 8-bit multi-perspective videos at 30 FPS, and multi-focal-plane image generation. We discuss scalability to terapixels and implications for near-to-eye displays.Titanium dioxide (TiO2) microring resonators (MRRs) with high quality factors (Qs) are demonstrated by using a new, to the best of our knowledge, bottom-up fabrication method. Pattern platforms with a T-shaped cross section are first defined by etching a thin top layer of silicon nitride and a thick bottom layer of silica and partially undercutting the silica. Then, TiO2 is deposited on the platforms to form the TiO2 waveguides and devices. TiO2 MRRs with different bending radii, waveguide widths, and gaps in the bus waveguide are fabricated and measured. The intrinsic Q(Q i n t ) is achieved to be ∼1.1×105 at the telecommunication wavelengths, corresponding to a bend waveguide loss of 3.9 dB/cm while the compact MRR with a radius of 10 µm can still sustain a Q i n t of ∼105. These results not only unfold the feasibilities of the proposed bottom-up method for fabricating TiO2 waveguides and MRRs with high Qs and compact footprints but also suggest a new approach for fabricating waveguides in other materials, of which direct etching is not easily accessible.We demonstrate coherent supercontinuum generation spanning over an octave from a silicon germanium-on-silicon waveguide using ∼200fs pulses at a wavelength of 4 µm. The waveguide is engineered to provide low all-normal dispersion in the TM polarization. We validate the coherence of the generated supercontinuum via simulations, with a high degree of coherence across the entire spectrum. Such a generated supercontinuum could lend itself to pulse compression down to 22 fs.To fully utilize the functions of a center-wavelength-sweeping pulse train generated by a free-space angular-chirp-enhanced delay optical layout for a probe laser pulse in sequentially timed all-optical mapping photography (STAMP), we introduced an integral field spectroscopy (IFS) method using a microlens array (MLA) to produce hyperspectral images, referring to the technique as lens array (LA)-STAMP. Compared with the previous STAMP utilizing spectral filtering where a bandpass filter generated hyperspectral images, LA-STAMP achieved much higher optical throughput. In a prototype setup, we used a 60×60 MLA and demonstrated single-shot burst imaging of a femtosecond laser-induced ablation process on a glass surface with 300 ps frame intervals in a 1.8 ns time window. Each frame image was constructed by assembling spectrally dispersed 36×36 monochromatic segments distributed by each lenslet on 5×5 pixels of a CCD camera. The spatial resolution was ∼4.4µm, which was determined by the MLA’s pitch and the magnification of the microscope lens.