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1. Extrinsic doping of Hg ₂ GeTe ₄ in the face of defect compensation and phase competition

   https://doi.org/10.1039/D3TC00209H  

   Porter, Claire E.; Qu, Jiaxing; Cielsielski, Kamil; Ertekin, Elif; Toberer, Eric S. (July 2023, Journal of Materials Chemistry C)

   Computation-guided selection of dopants enables the transformation of Hg₂GeTe₄from intrinsic to degenerate carrier concentrations and the thermoelectric performance is assessed experimentally. 

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2. A New Parameterization for Finding Solutions for Microlensing Exoplanet Light Curves

   https://doi.org/10.1088/1538-3873/ad70d7  

   Hall, Kylie E; Yee, Jennifer C; Shin, In-Gu; Yang, Hongjing; Zhang, Jiyuan (September 2024, Publications of the Astronomical Society of the Pacific)

   Abstract The gravitational microlensing method of discovering exoplanets and multi-star systems can produce degenerate solutions, some of which require in-depth analysis to uncover. We propose a new parameter space that can be used to sample potential solutions more efficiently and is more robust at finding all degenerate solutions for the “central-resonant” caustic degeneracy. We identified two new parameters,kandh, that can be sampled in place of the mass ratios and separations of the systems under analysis to identify degenerate solutions. The parameterkis related to the size of the central caustic, Δξ_c, whilehis related to the distance of a point along thekcontour from log(s) = 0, wheresis the projected planet-host separation. In this work, we present the characteristics of these parameters and the tests we conducted to prove their efficacy. 

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3. A Molecular Compound for Highly Selective Purification of Ethylene

   https://doi.org/10.1002/anie.202109338  

   Noonikara‐Poyil, Anurag; Cui, Hui; Yakovenko, Andrey A.; Stephens, Peter W.; Lin, Rui‐Biao; Wang, Bin; Chen, Banglin; Dias, H. V. Rasika (November 2021, Angewandte Chemie International Edition)

   Abstract Purification of C₂H₄from an C₂H₄/C₂H₆mixture is one of the most challenging separation processes, which is achieved mainly through energy‐intensive, cryogenic distillation in industry. Sustainable, non‐distillation methods are highly desired as alternatives. We discovered that the fluorinated bis(pyrazolyl)borate ligand supported copper(I) complex {[(CF₃)₂Bp]Cu}₃has features very desirable in an olefin–paraffin separation material. It binds ethylene exclusively over ethane generating [(CF₃)₂Bp]Cu(C₂H₄). This molecular compound exhibits extremely high and record ideal adsorbed solution theory (IAST) C₂H₄/C₂H₆gas separation selectivity, affording high purity (>99.5 %) ethylene that can be readily desorbed from separation columns. In‐situ PXRD provides a “live” picture of the reversible conversion between [(CF₃)₂Bp]Cu(C₂H₄) and the ethylene‐free sorbent in the solid‐state, driven by the presence or removal of C₂H₄. Molecular structures of trinuclear {[(CF₃)₂Bp]Cu}₃and mononuclear [(CF₃)₂Bp]Cu(C₂H₄) are also presented. 

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4. KMT-2021-BLG-1150Lb: Microlensing planet detected through a densely covered planetary-caustic signal

   https://doi.org/10.1051/0004-6361/202346596  

   Han, Cheongho; Jung, Youn Kil; Bond, Ian A; Gould, Andrew; Chung, Sun-Ju; Albrow, Michael D; Hwang, Kyu-Ha; Ryu, Yoon-Hyun; Shin, In-Gu; Shvartzvald, Yossi; et al (July 2023, Astronomy & Astrophysics)

   Aims.Recently, there have been reports of various types of degeneracies in the interpretation of planetary signals induced by planetary caustics. In this work we check whether such degeneracies persist in the case of well-covered signals by analyzing the lensing event KMT-2021-BLG-1150, the light curve of which exhibits a densely and continuously covered short-term anomaly. Methods.In order to identify degenerate solutions, we thoroughly investigated the parameter space by conducting dense grid searches for the lensing parameters. We then checked the severity of the degeneracy among the identified solutions. Results.We identify a pair of planetary solutions resulting from the well-known inner-outer degeneracy, and find that interpreting the anomaly is not subject to any degeneracy other than the inner-outer degeneracy. The measured parameters of the planet separation (normalized to the Einstein radius) and mass ratio between the lens components are (s,q)_in~ (1.297, 1.10 × 10⁻³) for the inner solution and (s,q)_out~ (1.242, 1.15 × 10⁻³) for the outer solution. According to a Bayesian estimation, the lens is a planetary system consisting of a planet with a massM_p= 0.88_−0.36^+0.38M_jand its host with a massM_h= 0.73_−0.30^+0.32M_⊙lying toward the Galactic center at a distanceD_L= 3.8_−1.2^+1.3kpc. By conducting analyses using mock data sets prepared to mimic those obtained with data gaps and under various observational cadences, we find that gaps in data can result in various degenerate solutions, while the observational cadence does not pose a serious degeneracy problem as long as the anomaly feature can be delineated. 

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5. Vertical-cavity surface-emitting phase shifter

   https://doi.org/10.1364/OE.497606  

   Almutairi, Dhaifallah; Johnson, Karl; Smolyaninov, Alexei; Grieco, Andrew; Fainman, Yeshaiahu (September 2023, Optics Express)

   This study proposes a novel technique for a 2D beam steering system using hybrid plasmonic phase shifters with a cylindrical configuration in a 2D periodic array suitable for LIDAR applications. A nanoscale VCSEP design facilitates a sub-wavelength spacing between individual phase shifters, yielding an expanded field of view and side lobes suppression. The proposed design includes a highly doped sub-micron silicon pillar covered by a thin layer of nonlinear material and an additional conductive metal layer. Characterization of a single VCSEP demonstrated a Free Spectral Range (FSR) of 53.28 ± 2.5 nm and a transmission variation of 3 dB, with V_πL equal to 0.075 V-mm. 

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