BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Thomas Barthel (Duke) DTSTART:20201116T190000Z DTEND:20201116T200000Z DTSTAMP:20260423T023009Z UID:UKYhepth/20 DESCRIPTION:Title: Entanglement entropy of energy eigenstates follows a universal scaling f unction\nby Thomas Barthel (Duke) as part of Theoretical Physics Semin ars (Kentucky)\n\n\nAbstract\nWe consider the entanglement entropies of en ergy eigenstates in quantum many-\nbody systems. For the typical models th at allow for a field-theoretical\ndescription of the long-range physics\, we find that the entanglement entropy of\n(almost) all eigenstates is desc ribed by a single scaling function. This is\npredicated on the validity of the weak or strong eigenstate thermalization\nhypothesis (ETH)\, which th en implies that the scaling functions can be deduced\nfrom subsystem entro pies of thermal ensembles. The scaling functions describe\nthe full crosso ver from the groundstate entanglement regime for low energies\nand small s ubsystem size (area or log-area law) to the extensive volume-law\nregime f or high energies or large subsystem size. For critical 1d systems\, the\ns caling function follows from conformal field theory (CFT). We use it to al so\ndeduce the scaling function for Fermi liquids in d>1 dimensions. These \nanalytical results are complemented by numerics for large non-interactin g\nsystems of fermions in d=1\,2\,3 and the harmonic lattice model in d=1\ ,2.\nLastly\, we demonstrate ETH for entanglement entropies and the validi ty of the\nscaling arguments in integrable and non-integrable interacting spin chains. In\nparticular\, we analyze the XXZ and transverse-field Isin g models with and\nwithout next-nearest-neighbor interactions.\n\nReferenc es: arXiv:1905.07760\, arXiv:1912.10045\, arXiv:2010.07265\n LOCATION:https://researchseminars.org/talk/UKYhepth/20/ END:VEVENT END:VCALENDAR