Quasiparticle metamorphosis in the random t-J model

Abstract

Motivated by the pseudogap-Fermi liquid transition in doped Mott insulators, we examine the excitations of a $t$-$J$ model with random and all-to-all hopping and exchange. The stability of quasiparticles such as spin-1/2 fermions, spin-1 magnons, and emergent Jordan-Wigner (JW) spinless fermions is cast as a problem of localization in the many-body Hilbert space, which is studied by the FEAST eigensolver algorithm. At low dopings, magnons and JW fermions are better defined than spin-1/2 fermions, which are unstable. Upon crossing a critical value of doping around $p_c$ = 1/3, their stabilities are interchanged. Near the critical doping, these quasiparticles are all found to be ill-defined. The critical point is thus associated with a localization transition in the many-body Hilbert space

7 pages, 6 figures

References in corpus (6)

• A Density Matrix-based Algorithm for Solving Eigenvalue Problems
• How bad metals turn good: spectroscopic signatures of resilient quasiparticles
• Fractional excitations in the square-lattice quantum antiferromagnet
• Giant thermal Hall conductivity from neutral excitations in the pseudogap phase of cuprates
• Microscopic spinon-chargon theory of magnetic polarons in the t-J model
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Cited by in corpus (3)

• Unravelling the Nature of Spin Excitations Disentangled from Charge Contributions in a Doped Cuprate Superconductor
• A unified theory of strong coupling Bose polarons: From repulsive polarons to non-Gaussian many-body bound states
• The fate of the spin polaron in the 1D antiferromagnets