Sara Murciano (Université Paris-Saclay), Boundary Transitions from a Single Round of Measurements on Critical States

Wednesday 1 Apr 2026, 11:15 → 12:30 Europe/Stockholm

Albano 3: 6228 - Mega (22 seats) (Albano Building 3)

Abstract: Quantum critical systems constitute appealing platforms for the exploration of novel measurement-induced phenomena due to their innate sensitivity to perturbations. Exploiting boundary conformal field theory techniques, we study the impact of measurement on Ising chains using an explicit protocol, whereby uncorrelated ancillae are entangled with the critical chain and then projectively measured. These measurements can modify the Ising order-parameter scaling dimension in a significant way, and we show that varying the measurement basis can induce a flow towards different conformal invariant boundary conditions. We further investigate the impact of measurements on the tricritical Ising and three-state Potts model, finding how they can trigger a non-trivial flow to different boundary conditions. The main upshot is that a single round of measurements can, upon rotating the measurement basis, induce non-trivial transitions separating regimes displaying universal characteristics governed by distinct boundary conformal field theories.