Fermion models with quasilocal interaction around polycritical points

We develop a procedure which systematically generates all conserved operators in the disordered models of interacting fermions. Among these operators, we identify and count the independent and local integrals of motion (LIOM), which represent the hallmark of the many-body localization (MBL). The method is tested first on the prototype disordered chain of interacting spinless fermions. As expected for full MBL, we find for large enough disorder ${N}_{M}={2}^{M}\ensuremath{-}1$ independent and quasilocal LIOM with support on $M$ consecutive sites. On the other hand, the study of the disordered Hubbard chain reveals that ${3}^{M}\ensuremath{-}1<{N}_{M}\ensuremath{\lesssim}{4}^{M}/2$, which is less than required for full MBL but much more than in the case of spinless fermions.We develop a procedure which systematically generates all conserved operators in the disordered models of interacting fermions. Among these operators, we identify and count the independent and local integrals of motion (LIOM), which represent the hallmark of the many-body localization (MBL). The method is tested first on the prototype disordered chain of interacting spinless fermions. As expected for full MBL, we find for large enough disorder ${N}_{M}={2}^{M}\ensuremath{-}1$ independent and quasilocal LIOM with support on $M$ consecutive sites. On the other hand, the study of the disordered Hubbard chain reveals that ${3}^{M}\ensuremath{-}1<{N}_{M}\ensuremath{\lesssim}{4}^{M}/2$, which is less than required for full MBL but much more than in the case of spinless fermions.

arXiv:1708.08931Physical review. B./Physical review. BFeb 28, 201859 citations

Interacting Fermions in Quasi-1D

Ya-Ting Chang, Ruwan Senaratne, Danyel Cavazos-Cavazos +1 more

Bulletin of the American Physical SocietyJun 2, 20210 citations

Symmetry-resolved quasilocal entanglement as a key to Mott and pseudogap physics in plaquette CDMFT

Gabriele Bellomia, Carlos Mejuto-Zaera, Massimo Capone +1 more

In order to identify intrinsic quantum resources in strongly interacting fermionic systems, we introduce a symmetry resolution of the parity-superselected two-site entanglement, as measured by both the fermionic negativity and the relative entropy of entanglement. We discuss how the symmetry resolution can be extended also to the full entanglement in pure and mixed two-site states. We apply our recipe to the Hubbard model, first for a dimer, and then for a plaquette cluster dynamical mean-field theory, an established method tailored to accurately capture short-range correlations. Following the evolution of the model through the interaction- and density-driven Mott transitions at zero temperature, we highlight how the three symmetry-resolved components of the two-site entanglement probe different key aspects of Mott and pseudogap physics.In order to identify intrinsic quantum resources in strongly interacting fermionic systems, we introduce a symmetry resolution of the parity-superselected two-site entanglement, as measured by both the fermionic negativity and the relative entropy of entanglement. We discuss how the symmetry resolution can be extended also to the full entanglement in pure and mixed two-site states. We apply our recipe to the Hubbard model, first for a dimer, and then for a plaquette cluster dynamical mean-field theory, an established method tailored to accurately capture short-range correlations. Following the evolution of the model through the interaction- and density-driven Mott transitions at zero temperature, we highlight how the three symmetry-resolved components of the two-site entanglement probe different key aspects of Mott and pseudogap physics.

cond-mat.str-elCross-listedarXiv:2610.34470Oct 27, 20260 citations

Fermions Acting on Quasi-local Operators in the XXZ Model

Michio Jimbo, Tetsuji Miwa, Feodor Smirnov

Springer proceedings in mathematics & statisticsDec 4, 20126 citations

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consecutive sites. On the other hand, the study of the disordered Hubbard chain reveals that ${3}^{M}\ensuremath{-}1<{N}_{M}\ensuremath{\lesssim}{4}^{M}/2$, which is less than required for full MBL but much more than in the case of spinless fermions.