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We build a compressive imaging system that can reconstruct high-speed videos of two fields-of-view by capturing a single frame. A single digital micromirror device is employed to implement high-speed modulation simultaneously on both scenes in a manner that does not compromise spatial resolution. We utilize deep denoising priors in the plug-and-play framework for efficient reconstruction. Two spatial-temporal data cubes, each with the size $ 650 \times 650 \times 20 $650×650×20, are reconstructed from a single two-dimensional spatial measurement.We present a dual-color-soliton fiber laser at two different wavebands by nonlinear multimode interference. A saturable absorber (SA) with single-mode-multimode (MMF)-single-mode fiber structure is placed in the common branch shared by two sub-cavities. Saturable absorption effects can be simultaneously satisfied at 1.5 and 2 µm at a proper length of the MMF. Dual-color solitons can still remain, even by slightly tuning the length of the MMF. The periodical characteristic of this SA provides a flexible choice of MMF length, making it simple for simultaneous mode locking (SML) at two separate wavebands in practice. Our approach not only paves the way for SML at two or more wavebands by the MMF but also could lead to significant applications in pump-probe spectroscopy.By utilizing notions from statistical mechanics, we develop a general and self-consistent theoretical framework capable of describing any weakly nonlinear optical multimode system involving conserved quantities. We derive the fundamental relations that govern the grand canonical ensemble through maximization of the Gibbs entropy at equilibrium. In this classical picture of statistical photo-mechanics, we obtain analytical expressions for the probability distribution, the grand partition function, and the relevant thermodynamic potentials. Our results universally apply to any other weakly nonlinear multimode bosonic system.LED array microscopy is an emerging platform for computational imaging with significant utility for biological imaging. Existing LED array systems often exploit transmission imaging geometries of standard brightfield microscopes that leave the rich backscattered field undetected. This backscattered signal contains high-resolution sample information with superb sensitivity to subtle structural features that make it ideal for biological sensing and detection. Here, we develop an LED array reflectance microscope capturing the sample’s backscattered signal. In particular, we demonstrate multimodal brightfield, darkfield, and differential phase contrast imaging on fixed and living biological specimens including Caenorhabditis elegans (C. elegans), zebrafish embryos, and live cell cultures. Video-rate multimodal imaging at 20 Hz records real time features of freely moving C. elegans and the fast beating heart of zebrafish embryos. Irpagratinib mouse Our new reflectance mode is a valuable addition to the LED array microscopic toolbox.A photonic analog-to-digital converter (ADC) scheme based on multi-wavelength sampling and balanced detection is proposed and experimentally demonstrated. In the approach, a power-weighted multi-wavelength pulsed source is employed to implement sampling, a dispersion element is used to realize temporal walk-off of multi-wavelength pulses, and a thresholding module is applied to implement serial thresholding. The principles of quantization and encoding are similar to that of an electronic flash ADC, but the serial implementation in the given approach avoids the use of large numbers of comparators. A proof-of-concept experiment with three wavelengths is successfully demonstrated. We also discuss the feasibility of the approach and the design of non-uniform quantization by properly setting the power ratio of the multi-wavelength pulses.We determine the optical phase $ \psi $ψ (dynamic and geometric) introduced by a system described by an inhomogeneous Jones matrix. We show that there are two possible scenarios (a) $ \psi $ψ has a finite range of $ \psi \in [\psi _\min ,\psi _\max ] $ψ∈[ψmin,ψmax]. We calculate both limits and their corresponding polarization states analytically. (b) $ \psi $ψ spans the full range of $ \psi \in ( – \pi ,\pi ] $ψ∈(-π,π]. This scenario leads to the existence of two input polarization states whose output states are orthogonal. We call these states ortho-transmission states (OTSs) and find them analytically. We study the inverse problem of designing an optical system with OTSs given by the user.We report on an all-fiber mode-locked repetition-rate-switch pulse operation in a Yb-doped fiber laser based on a polarization rotation vector soliton. The polarization controller (PC) in a fiber loop and a polarization-dependent isolator at the output port are incorporated into the laser resonator at the switch of the repetition rate. By adjusting the PC in the cavity, the mode locking can be switched between the fundamental repetition rate and half of it with a tiny pulse width change. Also, the halved pulse exhibits unique properties a huge promotion in energy and peak power. To the best of our knowledge, this is the first all-fiber seed source with a passive switch of the repetition rate based on a vector soliton.By engineering atomic geometries composed of nearly 1000 atomic segments embedded in micro-resonators, we observe Bragg resonances induced by the atomic lattice at the telecommunication wavelength. The geometrical arrangement of erbium atoms into a lattice inside a silicon nitride (SiN) microring resonator reduces the scattering loss at a wavelength commensurate with the lattice. We confirm dependency of light emission to the atomic positions and lattice spacing and also observe Fano interference between resonant modes in the system.The BB84-based quantum key distribution system is limited in high-speed and chip integration due to the requirement of preparing and measuring four states. Recently, the simplified BB84 protocol with preparation and measurement of only three states has showed the approximate secret key rate with standard BB84. However, the security proof is valid only under the collective attack and requires the basis-independent detection efficiency condition. Here, we provide a security proof against the coherent attack, which simultaneously removes the basis-independent detection efficiency condition. Importantly, the phase error rate formula is quite simple through subtle observation. We expect that the simplified BB84 protocol with the decoy-state method can be implemented widely in reality.