Friday Quantum Seminar: Zhi-Yuan Wei

Date
Fri, Apr 3, 2026 12:00 pm - 1:00 pm
Location
ATL 2400

Description

Title:  Measurement-enhanced entanglement in monitored superconductors
Speaker:  Zhi-Yuan Wei (QuICS)
Date & Time:  April 3, 2026, 12:00pm
Where to Attend:  ATL 2400

Monitored quantum dynamics can exhibit entanglement phase transitions driven by the competition between unitary evolution and measurement. A common expectation is that LOCC measurements do not increase steady-state entanglement in such settings. We challenge this view by studying the dynamics of one-dimensional fermions (system size L) governed by a BCS Hamiltonian with gap Δ and subjected to on-site, spin-selective number measurements at rate p. Using exact Gaussian-state simulations and a quasiparticle analysis, we find that for Δ>0 the steady-state entanglement S increases with p over a finite interval 0 0 and small finite p, implying that the measurement-enhanced entanglement vanishes (i.e., p_th→0) in the thermodynamic limit.

Pizza and drinks will be served after the seminar in ATL 2117.