Separability as a window into many-body mixed-state phases

          @misc{ scivideos_PIRSA:24050028,
            doi = {10.48660/24050028},
            url = {https://pirsa.org/24050028},
            author = {Grover, Tarun},
            keywords = {Quantum Information},
            language = {en},
            title = {Separability as a window into many-body mixed-state phases},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2024},
            month = {may},
            note = {PIRSA:24050028 see, \url{https://scivideos.org/pirsa/24050028}}
          }
          

Abstract

Ground states as well as Gibbs states of many-body quantum Hamiltonians have been studied extensively for some time. In contrast, the landscape of mixed states that do not correspond to a system in thermal equilibrium is relatively less explored. In this talk I will motivate a rather coarse characterization of mixed quantum many-body states using the idea of "separability", i.e., whether a mixed state can be expressed as an ensemble of short-range entangled pure states. I will discuss several examples of decoherence-driven phase transitions from a separability viewpoint, and argue that such a framework also provides a potentially new view on Gibbs states. Based on work with Yu-Hsueh Chen. References: 2309.11879, 2310.07286, 2403.06553.