Author(s): Xiaojian Huang, Lei Xiao, Bingzi Huo, Xiaowei Wang, Stefano Longhi, and Peng Xue Dynamical phase transitions in open quantum systems govern how nonequilibrium states relax toward a stationary state. We study these transitions experimentally using a discrete-time photonic quantum walk on a three-node graph. A tunable synthetic gauge flux and calibrated dephasing allow us to contr… [Phys. Rev. Lett. 137, 110804] Published Fri Sep 11, 2026