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1. Foundry-fabricated photonic integrated circuit for flex-grid entanglement distribution

   https://doi.org/10.1364/CLEO_AT.2024.JW2A.139  

   Miloshevsky, Alexander; Lu, Hsuan-Hao; Cohen, Lucas M; Myilswamy, Karthik V; Fatema, Saleha; Alshowkan, Muneer; Weiner, Andrew M; Lukens, Joseph M (January 2024, Optica Publishing Group)

   We demonstrate a silicon photonic integrated circuit fabricated through the CMOS manufacturing process, which features a bidirectionally pumped microring to achieve over 116 high-fidelity polarization entangled channels covering the entire optical C+L-band for flex-grid entanglement distribution. 

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2. Loaded Microstrip Network Transmision-Line Metamaterials on an Irregular Grid

   https://doi.org/10.1109/AP-S/USNC-URSI47032.2022.9886547  

   Maurer, Tina E.; Kwon, Do-Hoon (July 2022, 2022 IEEE International Symposium on Antennas and Propagation)

   A planar loaded microstrip network metamaterial on an irregular grid for modeling 2-D electromagnetic environment in TE polarization is presented. The technique is applied to a Luneburg lens example toward printed circuit implementation and verification. 

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3. Recent developments in tornado theory and observations

   https://doi.org/10.1088/1361-6633/ad7f6a  

   Rotunno, Richard; Bluestein, Howard B (October 2024, Reports on Progress in Physics)

   Abstract This article critically reviews research on tornado theory and observations over the last decade. From the theoretical standpoint, the major advances have come through improved numerical-simulation models of supercell convective storms, which contain the tornado’s parent circulation. These simulations are carried out on a large domain (to capture the supercell’s circulation system), but with high grid resolution and improved representations of sub-grid physics (to capture the tornado). These simulations offer new insights into how and why tornadoes form in some supercells, but not others. Observational advances have come through technological improvements of mobile Doppler radars capable of rapid scanning and dual-polarization measurements, which offer a much more accurate view of tornado formation, tornado structure, and the tornado’s place within its parent supercell. 

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4. Multiple Metamaterial Pattern Integration for Polarization Selective Photodetector Applications

   https://doi.org/10.1557/adv.2018.43  

   Shemelya, Corey; Pfiester, Nicole A.; DeMeo, Dante; Rotter, Thomas; Balakrishnan, Ganesh; Vandervelde, Thomas E. (January 2018, MRS Advances)

   ABSTRACT Interest in active metamaterial (MM) devices has recently increased due to their potential for tunable, switchable, and scalable optical responses. More specifically, a dynamic, on-chip MM polarizer has applications ranging from material characterization to sensing without the need for cumbersome external filters. This work demonstrates efforts to optimize MM devices for dynamic polarization filtering by combining elements from split-ring resonators, wire-pairs, and fishnet patterns. The polarization grid has been designed to operate under an applied voltage with simulated on/off ratios of 75% and dynamic polarization selectivity of 70%. Samples have been fabricated using epitaxial GaAs on sapphire with various n-type doping concentrations to approximate electrical tuning. 

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5. Line Polarization of Si ii λ 6355 Å in Type Ia Supernovae: A New Statistical Approach to Probe the Explosion Physics and Diversity

   https://doi.org/10.3847/2041-8213/ae27c8  

   Cikota, Aleksandar; Hoeflich, Peter; Baade, Dietrich; Patat, Ferdinando; Wang, Lifan; Wheeler, J Craig; Yang, Yi; Fereidouni, Elham; Mishra, Divya (December 2025, The Astrophysical Journal Letters)

   Abstract Spectropolarimetry provides a unique probe of ejecta asphericities, offering direct insights into the underlying explosion physics of Type Ia supernovae (SNe Ia). We analyze the statistical properties of premaximum spectropolarimetric data for 24 SNe Ia observed with the FOcal Reducer and low dispersion Spectrograph on the Very Large Telescope, focusing on the Siiiλ6355 Å line. Previous studies have revealed a correlation between the peak Siiipolarization degree and the expansion velocity. Here, we combine these observations with multidimensional nonthermodynamical equilibrium radiative transfer simulations. We consider two asphericity classes: (i) lopsided abundance distributions produced by off-center delayed-detonation transitions in near-M_Chwhite dwarfs (WDs) or, for example, WD collisions (class I), and (ii) global axisymmetric density asphericities such as those arising from explosions of rapidly rotating WDs or mergers (class II). Our model grid spans normal to subluminous SNe Ia and successfully reproduces the observed Siiivelocity–polarization trend, with higher velocities associated with stronger asphericities. Consistent with observations, transitional SNe Ia and the faint end of the normal SN Ia population show the highest Siiipolarization and are best explained by class I scenarios. In contrast, subluminous SNe Ia are dominated by class II asphericities, characterized by lower Siiipolarization but significant continuum polarization. The observed distribution of Siiipolarization depends on both the observer’s viewing angleθand the intrinsic asphericity. Statistical analysis of these spectropolarimetric snapshots enables the separation of class I and class II contributions and highlights the intrinsic diversity among SNe Ia. Our results imply viewing-angle-dependent luminosities in our local sample, which may have implications when using high-redshift SNe Ia as evidence for the need for nonstandard cosmology. 

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