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conference presentation abstract 

Using silicon-nitride microresonators with integrated Moiré-Bragg gratings to suppress parasitic nonlinear processes, we demonstrate on-chip frequency conversion to a single idler tone with a record-high 71% efficiency using Bragg scattering four-wave-mixing. 

Aqueous electrolytes are the leading candidate to meet the surging demand for safe and low-cost storage batteries. Aqueous electrolytes facilitate more sustainable battery technologies due to the attributes of being nonflammable, environmentally benign, and cost effective. Yet, water’s narrow electrochemical stability window remains the primary bottleneck for the development of high-energy aqueous batteries with long cycle life and infallible safety. Water’s electrolysis leads to either hydrogen evolution reaction (HER) or oxygen evolution reaction (OER), which causes a series of dire consequences, including poor Coulombic efficiency, short device longevity, and safety issues. These are often showstoppers of a new aqueous battery technology besides the low energy density. Prolific progress has been made in the understanding of HER and OER from both catalysis and battery fields. Unfortunately, a systematic review on these advances from a battery chemistry standpoint is lacking. This review provides in-depth discussions on the mechanisms of water electrolysis on electrodes, where we summarize the critical influencing factors applicable for a broad spectrum of aqueous battery systems. Recent progress and existing challenges on suppressing water electrolysis are discussed, and our perspectives on the future development of this field are provided. 

Cross quadrature correlations are observed from the spectral matrices of two-mode bright states generated in an integrated optical parametric oscillator. We attribute degradation of amplitude difference squeezing with increasing pump intensities to this effect. 

We present the strongest experimental limits to date on the mixing angle, $\theta$ , with which a new scalar particle, $S$ , mixes with the Higgs field in the mass range $110\mathrm{MeV}<m_S<155\mathrm{MeV}$ . This result uses the MicroBooNE liquid argon time projection chamber to search for decays of these Higgs-portal scalar particles through the $S\to e^{+}{e}^{-}$ channel with the decays of kaons in the NuMI neutrino beam acting as the source of the scalar particles. The analysis uses an exposure of $2.01\times {10}^{21}$ protons on target of NuMI beam data including periods when the beam focusing system was configured to focus positively charged hadrons and separate periods when negatively charged hadrons were focused. The analysis searches for scalar particles produced from kaons decaying in flight in the beam’s decay volume and at rest in the target and absorber. At $m_S=125\mathrm{MeV}$ ( $m_S=150\mathrm{MeV}$ ) we set a limit of $\theta <3.19\times {10}^{-4}$ ( $\theta <2.79\times {10}^{-4}$ ) at the 95% confidence level. 

In review. 

As promising alternatives to lithium-ion batteries, rechargeable anion-shuttle batteries (ASBs) with anions as charge carriers stand out because of their low cost, long cyclic lifetime, and/or high energy density. In this review, we provide for the first time, comprehensive insights into the anion shuttling mechanisms of ASBs, including anion-based rocking-chair batteries (ARBs), dual-ion batteries (DIBs), including insertion-type, conversion-type, and conversion- insertion-type, and reverse dual-ion batteries (RDIBs). Thereafter, we review the latest progresses and challenges regarding electrode materials and electrolytes for ASBs. In addition, we summarize the existing dilemmas of ASBs and outline the perspective of ASB technology for future grid storage. 

https://www.thearcticinstitute.org/infrastructure-community-resilience-changing-arctic-status-challenges-research-needs/