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1. Snapshot phase-shifting diffraction phase microscope

   https://doi.org/10.1364/OL.394033  

   Tian, Xiaobo; Liang, Rongguang (June 2020, Optics Letters)

   We propose a novel and simple snapshot phase-shifting diffraction phase microscope with a polarization grating and spatial phase-shifting technology. Polarization grating separates the incident beam into left and right circular polarization beams, one of which is used as the reference beam after passing through a pinhole. Four phase-shifted interferograms can be captured simultaneously from the polarization camera to reconstruct the high spatial resolution phase map. The principle is presented in this Letter, and the performance of the proposed system is demonstrated experimentally. Due to the near-common-path configuration and snapshot feature, the proposed system provides a feasible way for real-time quantitative phase measurement with minimal sensitivity to vibration and thermal disturbance. 

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2. Low-coherence snapshot phase-shifting diffraction phase microscope

   https://doi.org/10.1016/j.optlaseng.2023.107618  

   Sun, Yuanyuan; Wang, Yihan; Wang, Daodang; Pau, Stanley; Liang, Rongguang (August 2023, Optics and Lasers in Engineering)

   We proposed a Wollaston-prism-based snapshot phase-shifting diffraction phase microscope (WP-SPDPM) for low-coherence snapshot quantitative phase imaging and videography. Wollaston prism separates two orthogonally linearly polarized beams with high degrees of polarization at a sufficiently small separation angle; one of the beams passing through a pinhole serves as the reference beam. Four phase-shifted interferograms are simultaneously acquired with a polarization camera to accurately retrieve a high spatial resolution phase map. The system is nearly common-path in configuration and can achieve a large slope range and high accuracy. In addition to the ability to resist environmental noise, the WP-SPDPM is suitable for phase measurement using low-coherence light. The accuracy and large measurable slope range of the proposed system is validated and compared experimentally with a commercial profilometer. We believe WP-SPDPM is a powerful tool for the accurate and robust quantitative phase measurement and has a significant potential of the real-time phase imaging. 

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3. Phase-separating pyrenoid proteins form complexes in the dilute phase

   https://doi.org/10.1038/s42003-022-04373-x  

   He, Guanhua; GrandPre, Trevor; Wilson, Hugh; Zhang, Yaojun; Jonikas, Martin C.; Wingreen, Ned S.; Wang, Quan (December 2023, Communications Biology)

   Abstract While most studies of biomolecular phase separation have focused on the condensed phase, relatively little is known about the dilute phase. Theory suggests that stable complexes form in the dilute phase of two-component phase-separating systems, impacting phase separation; however, these complexes have not been interrogated experimentally. We show that such complexes indeed exist, using an in vitro reconstitution system of a phase-separated organelle, the algal pyrenoid, consisting of purified proteins Rubisco and EPYC1. Applying fluorescence correlation spectroscopy (FCS) to measure diffusion coefficients, we found that complexes form in the dilute phase with or without condensates present. The majority of these complexes contain exactly one Rubisco molecule. Additionally, we developed a simple analytical model which recapitulates experimental findings and provides molecular insights into the dilute phase organization. Thus, our results demonstrate the existence of protein complexes in the dilute phase, which could play important roles in the stability, dynamics, and regulation of condensates. 

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4. A Multi-Phase Injection-Locked 8-Phase 17 GHz Clock Generator with 6b Phase Rotation for Multi-Phase Wireline Receivers

   https://doi.org/10.1109/ESSERC62670.2024.10719579  

   Zhou, Bob; Nikolić, Borivoje (September 2024, IEEE)

   A high frequency multi-phase clock generator circuit with a 6b phase rotator is presented for multi-phase wireline receivers. Multi-phase injection is used to efficiently generate and rotate 8 clock phases. Unlike prior rotator-based work, this work does not use time modulation, reducing the resulting deterministic jitter. A model is presented to study the nonlinearity introduced by the technique. The proposed 17 GHz circuit was implemented in the Intel 16 process and consumes 33 mW. The measured RMS jitter is $$\mathbf{9 8} \mathrm{fs}$$, and the measured DNLpp and INLpp are 1.26 and 4.05 LSB respectively. 

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5. Effects of the inert phase on solidification near a triple-phase line

   https://doi.org/10.1016/j.jcrysgro.2023.127438  

   Bagheri-Sadeghi, Nojan; Helenbrook, Brian T (January 2024, Journal of Crystal Growth)

   The local temperature solution near the triple-phase line of a solidifying front, its melt, and a surrounding inert phase was obtained analytically including all three phases and solidification kinetics. This analytical solution was validated using a three-phase numerical model of the horizontal ribbon growth of silicon and compared to a two-phase analysis that models the effect of the third phase (e.g. the gas) as an applied heat flux. Although the three-phase solutions have additional modes to represent the gas behavior, for many conditions the two-phase and three-phase models predicted consistent behaviors. However, introduction of a non-zero growth angle causes the gas phase heat fluxes to have strong gradients near the triple-phase line. Even with zero growth angle, there are conditions in which the two-phase and three-phase solutions are very different; one predicting infinite heat fluxes while the other predicts finite fluxes. This depended on the ratios of thermal conductivities, and the angle at which the solid-melt interface intersected the free surface. In particular, when the thermal conductivity of the inert phase was comparable to the melt or solid phases there were significant differences. 

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