BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//6.4.7.2//EN TZID:Europe/Paris X-WR-TIMEZONE:Europe/Paris BEGIN:VEVENT UID:0-1124@lptms.universite-paris-saclay.fr DTSTART;TZID=Europe/Paris:20260626T110000 DTEND;TZID=Europe/Paris:20260626T123000 DTSTAMP:20260619T085531Z URL:https://www.lptms.universite-paris-saclay.fr/seminars/informal-quantum -seminar-giacomo-bracci-testasecca/ SUMMARY:Informal Quantum Seminar: Giacomo Bracci Testasecca (SISSA) - Salle des séminaires du FAST et du LPTMS\, bâtiment Pascal n°530 - 26 Juin 2 6 11:00 DESCRIPTION:Semiclassical approach to the 2-dimensional quantum Heisenberg spin glass\nGiacomo Bracci Testasecca (SISSA)\n \;\nIn this seminar\, I will present recent results on the two-dimensional quantum Heisenberg mo del with bond disorder\, focusing on the emergence and nature of spin-glas s order in the quantum regime. Combining large-scale quantum simulations w ith a semiclassical expansion around classical states\, we identify an ext ended region of the zero temperature quantum phase diagram where conventio nal long-range magnetic order disappears in the thermodynamic limit\, whil e the overlap order parameter remains finite\, signalling a stable quantum spin-glass phase. The semiclassical analysis provides a microscopic chara cterization of this regime: at leading order\, the  quadratic spin-wave H amiltonian reveals that the character of low-energy excitations is control led by the correlations inherited from the underlying classical states. We find that the spin waves are weakly localized and discuss how the additio n of interactions leads to ergodicity restoring.\n\nBased on\nhttps://arxi v.org/abs/2507.05073\nhttps://arxiv.org/abs/2603.22077 CATEGORIES:seminars LOCATION:Salle des séminaires du FAST et du LPTMS\, bâtiment Pascal n°53 0\, rue André Riviere\, Orsay\, 91405\, France X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=rue André Riviere\, Orsay\ , 91405\, France;X-APPLE-RADIUS=100;X-TITLE=Salle des séminaires du FAST et du LPTMS\, bâtiment Pascal n°530:geo:0,0 END:VEVENT BEGIN:VTIMEZONE TZID:Europe/Paris X-LIC-LOCATION:Europe/Paris BEGIN:DAYLIGHT DTSTART:20260329T030000 TZOFFSETFROM:+0100 TZOFFSETTO:+0200 TZNAME:CEST END:DAYLIGHT END:VTIMEZONE END:VCALENDAR