BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Urs Schreiber (NYU Abu Dhabi) DTSTART:20251215T123000Z DTEND:20251215T133000Z DTSTAMP:20260422T140128Z UID:BilTop/130 DESCRIPTION:Title: Fragile Topological Phases and Topological Order of 2D Crystalline Chern Insulators\nby Urs Schreiber (NYU Abu Dhabi) as part of Bilkent Topolo gy Seminar\n\nLecture held in SA 141.\n\nAbstract\nWe apply methods of equ ivariant homotopy theory\, that may not previously have found due attentio n in condensed matter physics\, to classify first the fragile topological phases of 2D crystalline Chern insulator materials\, and second the potent ial topological order of their fractional cousins. We highlight that the p hases are given by the equivariant 2-Cohomotopy of the Brillouin torus of crystal momenta (with respect to wallpaper point group actions) — which\ , despite the attention devoted to crystalline Chern insulators\, seems no t to have been considered before. Arguing then that any topological order must be reflected in the adiabatic monodromy of gapped quantum ground stat es over the covariantized moduli space of these band topologies\, we compu te the latter in various examples where this group is non-abelian\, should that potential anyons must be localized in momentum space. We close with an outlook on the relevance for the search for topological quantum computi ng hardware.\n LOCATION:https://researchseminars.org/talk/BilTop/130/ END:VEVENT END:VCALENDAR