TY - JOUR AB - We demonstrate the failure of the adiabatic Born-Oppenheimer approximation to describe the ground state of a quantum impurity within an ultracold Fermi gas despite substantial mass differences between the bath and impurity species. Increasing repulsion leads to the appearance of nonadiabatic couplings between the fast bath and slow impurity degrees of freedom, which reduce the parity symmetry of the latter according to the pseudo Jahn-Teller effect. The presence of this mechanism is associated to a conical intersection involving the impurity position and the inverse of the interaction strength, which acts as a synthetic dimension. We elucidate the presence of these effects via a detailed ground-state analysis involving the comparison of ab initio fully correlated simulations with effective models. Our study suggests ultracold atomic ensembles as potent emulators of complex molecular phenomena. AU - Becker, A. AU - Koutentakis, Georgios AU - Schmelcher, P. ID - 15181 IS - 1 JF - Physical Review Research SN - 2643-1564 TI - Synthetic dimension-induced pseudo Jahn-Teller effect in one-dimensional confined fermions VL - 6 ER - TY - JOUR AB - Thermoelectric materials convert heat into electricity, with a broad range of applications near room temperature (RT). However, the library of RT high-performance materials is limited. Traditional high-temperature synthetic methods constrain the range of materials achievable, hindering the ability to surpass crystal structure limitations and engineer defects. Here, a solution-based synthetic approach is introduced, enabling RT synthesis of powders and exploration of densification at lower temperatures to influence the material's microstructure. The approach is exemplified by Ag2Se, an n-type alternative to bismuth telluride. It is demonstrated that the concentration of Ag interstitials, grain boundaries, and dislocations are directly correlated to the sintering temperature, and achieve a figure of merit of 1.1 from RT to 100 °C after optimization. Moreover, insights into and resolve Ag2Se's challenges are provided, including stoichiometry issues leading to irreproducible performances. This work highlights the potential of RT solution synthesis in expanding the repertoire of high-performance thermoelectric materials for practical applications. AU - Kleinhanns, Tobias AU - Milillo, Francesco AU - Calcabrini, Mariano AU - Fiedler, Christine AU - Horta, Sharona AU - Balazs, Daniel AU - Strumolo, Marissa J. AU - Hasler, Roger AU - Llorca, Jordi AU - Tkadletz, Michael AU - Brutchey, Richard L. AU - Ibáñez, Maria ID - 15182 JF - Advanced Energy Materials SN - 1614-6832 TI - A route to high thermoelectric performance: Solution‐based control of microstructure and composition in Ag2Se ER - TY - JOUR AB - Current knowledge suggests a drought Indian monsoon (perhaps a severe one) when the El Nino Southern Oscillation and Pacific Decadal Oscillation each exhibit positive phases (a joint positive phase). For the monsoons, which are exceptions in this regard, we found northeast India often gets excess pre-monsoon rainfall. Further investigation reveals that this excess pre-monsoon rainfall is produced by the interaction of the large-scale circulation associated with the joint phase with the mountains in northeast India. We posit that a warmer troposphere, a consequence of excess rainfall over northeast India, drives a stronger monsoon circulation and enhances monsoon rainfall over central India. Hence, we argue that pre-monsoon rainfall over northeast India can be used for seasonal monsoon rainfall prediction over central India. Most importantly, its predictive value is at its peak when the Pacific Ocean exhibits a joint positive phase and the threat of extreme drought monsoon looms over India. AU - Goswami, Bidyut B ID - 15165 IS - 5 JF - Geophysical Research Letters SN - 0094-8276 TI - A pre-monsoon signal of false alarms of Indian monsoon droughts VL - 51 ER - TY - JOUR AB - Reducing defects boosts room-temperature performance of a thermoelectric device AU - Navita, Navita AU - Ibáñez, Maria ID - 15166 IS - 6688 JF - Science SN - 0036-8075 TI - Electron highways are cooler VL - 383 ER - TY - JOUR AB - The extracellular matrix (ECM) serves as a scaffold for cells and plays an essential role in regulating numerous cellular processes, including cell migration and proliferation. Due to limitations in specimen preparation for conventional room-temperature electron microscopy, we lack structural knowledge on how ECM components are secreted, remodeled, and interact with surrounding cells. We have developed a 3D-ECM platform compatible with sample thinning by cryo-focused ion beam milling, the lift-out extraction procedure, and cryo-electron tomography. Our workflow implements cell-derived matrices (CDMs) grown on EM grids, resulting in a versatile tool closely mimicking ECM environments. This allows us to visualize ECM for the first time in its hydrated, native context. Our data reveal an intricate network of extracellular fibers, their positioning relative to matrix-secreting cells, and previously unresolved structural entities. Our workflow and results add to the structural atlas of the ECM, providing novel insights into its secretion and assembly. AU - Zens, Bettina AU - Fäßler, Florian AU - Hansen, Jesse AU - Hauschild, Robert AU - Datler, Julia AU - Hodirnau, Victor-Valentin AU - Zheden, Vanessa AU - Alanko, Jonna H AU - Sixt, Michael K AU - Schur, Florian KM ID - 15146 IS - 6 JF - Journal of Cell Biology SN - 0021-9525 TI - Lift-out cryo-FIBSEM and cryo-ET reveal the ultrastructural landscape of extracellular matrix VL - 223 ER -