4 research outputs found

    Evaporative cooling of trapped fermionic atoms

    Full text link
    We propose an efficient mechanism for the evaporative cooling of trapped fermions directly into quantum degeneracy. Our idea is based on an electric field induced elastic interaction between trapped atoms in spin symmetric states. We discuss some novel general features of fermionic evaporative cooling and present numerical studies demonstrating the feasibility for the cooling of alkali metal fermionic species 6^6Li, 40^{40}K, and 82,84,86^{82,84,86}Rb. We also discuss the sympathetic cooling of fermionic hyperfine spin mixtures, including the effects of anisotropic interactions.Comment: to be publishe

    Roadmap for Optical Tweezers 2023

    Get PDF
    Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nanoparticle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration

    The genetic architecture of the human cerebral cortex

    Get PDF
    The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder
    corecore