QuCoLiMa Talk - Sam Garratt - Measurements conspire nonlocally to restructure critical quantum states

Jun 27
27. June 2023 17:00 - 18:00


Sam Garratt – UC Berkeley


Measurements conspire nonlocally to restructure critical quantum states


I will discuss the effects of local measurements on critical quantum ground states. In critical states there are algebraic correlations between local observables and, as a consequence, local measurements can have highly nonlocal effects. This raises the possibility for a new class of collective phenomenon arising from the conspiracy of commuting measurements alone. In certain scenarios the post-measurement state has qualitatively different correlations to the original ground state, while in others the original correlations are robust, and I will discuss a sharp transition between these two regimes. Because there is no dynamics in the problem this behavior is robust to local decoherence, although a post-selection problem poses a barrier to their direct observation. I will show that resource-efficient probes are instead to be found in cross-correlations between experimental measurement results and simulations on classical computers.



All talks hybrid:

Mixture of on-site talks at the main sites of QuCoLiMa (Erlangen, Mainz, Saarbr?cken) as well as online talks. Regardless of where the talks are given, they are livestreamed via Zoom and can be watched from home/office or cooperatively in the following meeting rooms:

– Erlangen: Livestream/Presentation in Lecture hall HF + open sandwiches in the foyer afterwards

– Saarbr?cken: Livestream/Presentation in tba

– Mainz: Livestream/Presentation in tba



– – –

QuCoLiMa Talks are regular seminars of the collaborative research center TRR 306 QuCoLiMa (Quantum Cooperativity of Light and Matter), where (external) experts are invited to present their work.

More information at http://www.qucolima.de/talks