Por Pedro Ribeiro (CeFEMA and Physics Department, Instituto Superior Técnico, Universidade de Lisboa, Portugal).

When studying quantum phenomena outside of equilibrium, critical systems near continuous phase transitions are ideal candidates due to their high susceptibility to perturbations. However, understanding quantum critical phenomena in such non-equilibrium conditions remains a challenge, as traditional techniques often fall short. In this presentation, we will explore the concept of the single-particle affinity, a measure inspired by the effectiveness of quantum information-based tools in detecting phase transitions. Unlike other measures such as the quantum fidelity, the single-particle affinity is widely accessible and can serve as a versatile tool for identifying phase transitions that escape the traditional Landau's paradigm.  We will show that the single-particle affinity signals previously identified nonequilibrium phase transitions and has the potential to detect hitherto unknown phases in models of quantum matter far from equilibrium.