Inverted many-body mobility edge in a central qudit problem
arXiv:2008.12796 · doi:10.1103/PhysRevB.105.L060303
Abstract
Many interesting experimental systems, such as cavity QED or central spin models, involve global coupling to a single harmonic mode. Out-of-equilibrium, it remains unclear under what conditions localized phases survive such global coupling. We study energy-dependent localization in the disordered Ising model with transverse and longitudinal fields coupled globally to a -level system (qudit). Strikingly, we discover an inverted mobility edge, where high energy states are localized while low energy states are delocalized. Our results are supported by shift-and-invert eigenstate targeting and Krylov time evolution up to and respectively. We argue for a critical energy of the localization phase transition which scales as , consistent with finite size numerics. We also show evidence for a reentrant MBL phase at even lower energies despite the presence of strong effects of the central mode in this regime. Similar results should occur in the central spin- problem at large and in certain models of cavity QED.
References in corpus (13)
- Many body localization and thermalization in quantum statistical mechanics
- Localization of interacting fermions at high temperature
- Many-body localization edge in the random-field Heisenberg chain
- Strongly Interacting Polaritons in Coupled Arrays of Cavities
- Phenomenology of fully many-body-localized systems
- Periodically-driven quantum systems: Effective Hamiltonians and engineered gauge fields
- Many-body localization in periodically driven systems
- Many-body mobility edge in a mean-field quantum spin glass
- A Floquet Model for the Many-Body Localization Transition
- Many body localization with long range interactions
- Renormalization-group study of the many-body localization transition in one dimension
- Long-range spin-qubit interaction mediated by microcavity polaritons
- Localization dynamics in a centrally coupled system