Spin-Charge Separation in the $t-J$ Model: Magnetic and Transport Anomalies

Abstract

A real spin-charge separation scheme is found based on a saddle-point state of the $t-J$ model. In the one-dimensional (1D) case, such a saddle-point reproduces the correct asymptotic correlations at the strong-coupling fixed-point of the model. In the two-dimensional (2D) case, the transverse gauge field confining spinon and holon is shown to be gapped at {\em finite doping} so that a spin-charge deconfinement is obtained for its first time in 2D. The gap in the gauge fluctuation disappears at half-filling limit, where a long-range antiferromagnetic order is recovered at zero temperature and spinons become confined. The most interesting features of spin dynamics and transport are exhibited at finite doping where exotic {\em residual} couplings between spin and charge degrees of freedom lead to systematic anomalies with regard to a Fermi-liquid system. In spin dynamics, a commensurate antiferromagnetic fluctuation with a small, doping-dependent energy scale is found, which is characterized in momentum space by a Gaussian peak at ($\pi /a$, $\pi /a$) with a doping-dependent width ($\propto \sqrt{\delta }$, $\delta$ is the doping concentration). This commensurate magnetic fluctuation contributes a non-Korringa behavior for the NMR spin-lattice relaxation rate. There also exits a characteristic temperature scale below which a pseudogap behavior appears in the spin dynamics. Furthermore, an incommensurate magnetic fluctuation is also obtained at a {\em finite} energy regime. In transport, a strong short-range phase interference leads to an effective holon Lagrangian which can give rise to a series of interesting phenomena including linear-$T$ resistivity and $T^2$ Hall-angle. We discuss the striking similarities of these theoretical features with those found in the high-$T_c$ cuprates and give a

70 pages, RevTex, hard copies of 7 figures available upon request; minor revisions in the text and references have been made; To be published in July 1 issue of Phys. Rev. B52, (1995)

References in corpus (5)

• Theory of Two-Dimensional Quantum Heisenberg Antiferromagnets with a Nearly Critical Ground State
• Spin Gaps and Spin Dynamics in La_{2-x}Sr_xCuO_4 and YBa_2Cu_3O7_δ
• Theory of Nuclear Spin-Lattice Relaxation in La${}_2$CuO${}_4$ at High Temperatures
• Mott Transition in the Hubbard model
• Spin Susceptibility and Gap Structure of the Fractional-Statistics Gas

Cited by in corpus (22)

• Phase String Effect in the t-J Model: General Theory
• Angle-resolved photoemission spectroscopy with quantum gas microscopes
• Microscopic spinon-chargon theory of magnetic polarons in the t-J model
• Parton theory of ARPES spectra in anti-ferromagnetic Mott insulators
• Delocalization of electrons in a Random Magnetic Field
• Mutual-Chern-Simons effective theory of doped antiferromagnets
• Spin-Charge Separation in Angle-Resolved Photoemission Spectra
• Mean-Field Description of Phase String Effect in the $t-J$ Model
• Phase String Theory for Doped Antiferromagnets
• Spectral Functions of 1D Hubbard Rings with Varying Boundary Conditions
• Nature of spin-charge separation
• Anomalous spin-charge separation in a driven Hubbard system
• Bosonic resonating valence bond wave function for doped Mott insulators
• Spectral Properties of the Generalized Spin-Fermion Models
• Disorder-induced spin-charge separation in the 1-D Hubbard model
• Spectral function of one hole in several one-dimensional spin arrangements
• Kinetic magnetism in the crossover between the square and triangular lattice Fermi-Hubbard models
• Pairing in High Temperature Superconductors and Berry Phase
• Monopoles, confinement and charge localization in the t-J model with dilute holes
• Fractionalized Kohn-Sham Scheme for Strongly Correlated Electrons
• Emergence of Topological Fermi Liquid from a Strongly Correlated Bosonic System in Optical Superlattices
• Spin-charge separation for paired Dirac fermions in $(1+1)$ dimensions