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1. Thermally generated spin current in the topological insulator Bi ₂ Se ₃

   https://doi.org/10.1126/sciadv.adi4540  

   Jain, Rakshit; Stanley, Max; Bose, Arnab; Richardella, Anthony R.; Zhang, Xiyue S.; Pillsbury, Timothy; Muller, David A.; Samarth, Nitin; Ralph, Daniel C. (December 2023, Science Advances)

   We present measurements of thermally generated transverse spin currents in the topological insulator Bi₂Se₃, thereby completing measurements of interconversions among the full triad of thermal gradients, charge currents, and spin currents. We accomplish this by comparing the spin Nernst magneto-thermopower to the spin Hall magnetoresistance for bilayers of Bi₂Se₃/CoFeB. We find that Bi₂Se₃does generate substantial thermally driven spin currents. A lower bound for the ratio of spin current density to thermal gradient is $\frac{J_s}{{\mathbf{\nabla }}_{\mathit{x}}\mathit{T}}$= (4.9 ± 0.9) × 10⁶ $\left(\frac{\hslash }{2e}\right)\frac{\mathbf{A}{\mathbf{m}}^{-2}}{\mathbf{K}\text{μ}{\mathbf{m}}^{-1}}$, and a lower bound for the magnitude of the spin Nernst ratio is −0.61 ± 0.11. The spin Nernst ratio for Bi₂Se₃is the largest among all materials measured to date, two to three times larger compared to previous measurements for the heavy metals Pt and W. Strong thermally generated spin currents in Bi₂Se₃can be understood via Mott relations to be due to an overall large spin Hall conductivity and its dependence on electron energy. 

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2. Kinetics of the Topochemical Transformation of (PbSe) _m (TiSe ₂ ) _n (SnSe ₂ ) _m (TiSe ₂ ) _n to (Pb _0.5 Sn _0.5 Se) _m (TiSe ₂ ) _n

   https://doi.org/10.1021/jacs.8b10681  

   Sutherland, Duncan R.; Merrill, Devin R.; Ditto, Jeffrey; Moore, Daniel B.; Medlin, Douglas; Johnson, David C. (January 2019, Journal of the American Chemical Society)
3. Thermally Stable N ₂ -Intercalated WO ₃ Photoanodes for Water Oxidation

   https://doi.org/10.1021/ja3067622  

   Mi, Qixi; Ping, Yuan; Li, Yan; Cao, Bingfei; Brunschwig, Bruce S.; Khalifah, Peter G.; Galli, Giulia A.; Gray, Harry B.; Lewis, Nathan S. (November 2012, Journal of the American Chemical Society)
4. LLAMA: The M _BH – σ _⋆ relation of the most luminous local AGNs

   https://doi.org/10.1051/0004-6361/201936321  

   Caglar, Turgay; Burtscher, Leonard; Brandl, Bernhard; Brinchmann, Jarle; Davies, Richard I.; Hicks, Erin K.; Koss, Michael; Lin, Ming-Yi; Maciejewski, Witold; Müller-Sánchez, Francisco; et al (February 2020, Astronomy & Astrophysics)

   Context. The M BH – σ ⋆ relation is considered a result of coevolution between the host galaxies and their supermassive black holes. For elliptical bulge hosting inactive galaxies, this relation is well established, but there is still discussion concerning whether active galaxies follow the same relation. Aims. In this paper, we estimate black hole masses for a sample of 19 local luminous active galactic nuclei (AGNs; LLAMA) to test their location on the M BH – σ ⋆ relation. In addition, we test how robustly we can determine the stellar velocity dispersion in the presence of an AGN continuum and AGN emission lines, and as a function of signal-to-noise ratio. Methods. Supermassive black hole masses ( M BH ) were derived from the broad-line-based relations for H α , H β , and Pa β emission line profiles for Type 1 AGNs. We compared the bulge stellar velocity dispersion ( σ ⋆ ) as determined from the Ca II triplet (CaT) with the dispersion measured from the near-infrared CO (2-0) absorption features for each AGN and find them to be consistent with each other. We applied an extinction correction to the observed broad-line fluxes and we corrected the stellar velocity dispersion by an average rotation contribution as determined from spatially resolved stellar kinematic maps. Results. The H α -based black hole masses of our sample of AGNs were estimated in the range 6.34 ≤ log M BH  ≤ 7.75 M ⊙ and the σ ⋆CaT estimates range between 73 ≤  σ ⋆CaT  ≤ 227 km s −1 . From the so-constructed M BH  −  σ ⋆ relation for our Type 1 AGNs, we estimate the black hole masses for the Type 2 AGNs and the inactive galaxies in our sample. Conclusions. We find that our sample of local luminous AGNs is consistent with the M BH – σ ⋆ relation of lower luminosity AGNs and inactive galaxies, after correcting for dust extinction and the rotational contribution to the stellar velocity dispersion. 

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5. The potential for the evolution of thermally sensitive courtship behaviours in the treehopper, Enchenopa binotata

   https://doi.org/10.1111/jeb.14090  

   Sasson, Daniel; Agali, Uchechukwu; Brouk, Rachel; Hercules, Jacob; Kilmer, Joey; Macchiano, Anthony; Ola‐Ajose, Abisiola; Fowler‐Finn, Kasey (November 2022, Journal of Evolutionary Biology)