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1. Superconductivity in La2Ni2In

   https://doi.org/10.1103/PhysRevB.102.165125  

   Maiwald, J ; Mazin, I I ; Gurevich, A ; Aronson, M C ( October 2020 , Physical review)

   null (Ed.)

   We report here the properties of single crystals of La 2 Ni 2 In . Electrical resistivity and specific heat measurements concur with the results of density functional theory calculations, finding that La 2 Ni 2 In is a weakly correlated metal, where the Ni magnetism is almost completely quenched, leaving only a weak Stoner enhancement of the density of states. Superconductivity is observed at temperatures below 0.9 K. A detailed analysis of the field and temperature dependencies of the resistivity, magnetic susceptibility, and specific heat at the lowest temperatures reveals that La 2 Ni 2 In is a dirty type-II superconductor with likely s -wave gap symmetry. Nanoclusters of ferromagnetic inclusions significantly affect the subgap states resulting in a nonexponential temperature dependence of the specific heat C ( T ) at T ≪ T c . 

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2. Electrospray Ionization Tandem Mass Spectrometry With Collision Induced Dissociation of Uranyl Peroxide Nanoclusters Containing Various Uranyl Bridging Ligands

   https://doi.org/10.1002/chem.202300794  

   Rodriguez, Virginia G. ; Burns, Peter C. ( May 2023 , Chemistry – A European Journal)

   Electrospray ionization tandem mass spectrometry with collision‐induced dissociation (ESI‐MS/MS) was utilized to study the gas phase fragmentation of uranyl peroxide nanoclusters with hydroxo, peroxo, oxalate, and pyrophosphate bridging ligands. These nanoclusters fragment into uranium monomers and dimers with mass‐to‐charge (m/z) ratios in the 280–380 region. The gas phase fragmentation of each cluster studied yields a distinct UO₆⁻anion attributed to the cleavage of a uranyl ion bound to 2 peroxide groups, along with other anions that can be attributed to the initial composition of the nanoclusters.

    

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3. Effect of Fermi surface topology change on the Kagome superconductor CeRu2 under pressure

   https://doi.org/10.1016/j.mtphys.2023.101322  

   Deng, Liangzi ; Gooch, Melissa ; Liu, Hongxiong ; Salke, Nilesh P. ; Bontke, Trevor ; Shao, Sen ; You, Jingyang ; Schulze, Daniel J. ; Kumar, Ravhi ; Yin, Jia-Xin ; et al ( January 2024 , Materials Today Physics)

   - (Ed.)

   The cubic Laves phase compound CeRu2 with a Kagome substructure of Ru has been investigated to understand myriad fascinating phenomena resulting from competition among its various physical and geometric features. Such phenomena include flat bands, van Hove singularities, Dirac cones, reentrant superconductivity, magnetism, the Fulde–Ferrell–Larkin–Ovchinnikov state, valence fluctuations, time-irreversible anisotropic s-state superconductivity, etc. Extensive studies have thus been carried out since 1958 when the highly unusual coexistence of superconductivity and ferromagnetism was proposed for the mixed compounds (Ce,Gd)Ru2. Activity has accelerated in recent years due to increasing interest in topological states in superconductors. However, there has been little investigation of the mutual influence of these fascinating states. Therefore, we systematically investigated the superconductivity and possible Fermi surface topological change in CeRu2 via magnetic, resistivity, and structural measurements under pressure up to ~168 GPa. An unusual phase diagram that suggests an intriguing interplay between the compound’s superconducting order and Fermi surface topological order has been constructed. A resurgence in its superconducting transition temperature was observed above 28 GPa. Our experiments have identified a structural transition above 76 GPa and a few tantalizing phase transitions driven by high pressure. Our high-pressure results further suggest that superconductivity and Fermi surface topology in CeRu2 are strongly intertwined, 

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4. Josephson Detection of Time Reversal Symmetry Breaking s +/- is Superconductivity in SnTe Nanowires

   Trimble, C. ; Wei, M. T. ; Kalantre, S. S. ; Yuan, N. F. ; Liu, P. ; Cha, J. J. ; Fu, L. ; Williams, J. R. ( January 2019 , ArXiv.org)

   Exotic superconductivity, such as high TC, topological, and heavy-fermion superconductors, often rely on phase sensitive measurements to determine the underlying pairing. Here we investigate the proximity-induced superconductivity in nanowires of SnTe, where a s±is′ superconducting state is produced that lacks the time-reversal and valley-exchange symmetry of the parent SnTe. A systematic breakdown of three conventional characteristics of Josephson junctions -- the DC Josephson effect, the AC Josephson effect, and the magnetic diffraction pattern -- fabricated from SnTe nanowire weak links elucidates this novel superconducting state. Further, the AC Josephson effect reveals evidence of a Majorana bound state, tuned by a perpendicular magnetic field. This work represents the definitive phase-sensitive measurement of novel s±is′ superconductivity, providing a new route to the investigation of fractional vortices, topological superconductivity, topological phase transitions, and new types of Josephson-based devices. 

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5. Active emulsions in living cell membranes driven by contractile stresses and transbilayer coupling

   https://doi.org/10.1073/pnas.2123056119  

   Saha, Suvrajit ; Das, Amit ; Patra, Chandrima ; Anilkumar, Anupama Ambika ; Sil, Parijat ; Mayor, Satyajit ; Rao, Madan ( July 2022 , Proceedings of the National Academy of Sciences)

   The spatiotemporal organization of proteins and lipids on the cell surface has direct functional consequences for signaling, sorting, and endocytosis. Earlier studies have shown that multiple types of membrane proteins, including transmembrane proteins that have cytoplasmic actin binding capacity and lipid-tethered glycosylphosphatidylinositol-anchored proteins (GPI-APs), form nanoscale clusters driven by active contractile flows generated by the actin cortex. To gain insight into the role of lipids in organizing membrane domains in living cells, we study the molecular interactions that promote the actively generated nanoclusters of GPI-APs and transmembrane proteins. This motivates a theoretical description, wherein a combination of active contractile stresses and transbilayer coupling drives the creation of active emulsions, mesoscale liquid order (lo) domains of the GPI-APs and lipids, at temperatures greater than equilibrium lipid phase segregation. To test these ideas, we use spatial imaging of molecular clustering combined with local membrane order, and we demonstrate that mesoscopic domains enriched in nanoclusters of GPI-APs are maintained by cortical actin activity and transbilayer interactions and exhibit significant lipid order, consistent with predictions of the active composite model. 

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