Quasiparticle structure and coherent propagation in the {ital t}-{ital J}{sub {ital z}}-{ital J}{sub {perpendicular}} model

Journal Article · Mon Jan 01 04:00:00 EST 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.53.911· OSTI ID:434524

Gan, J; Hedegard, P ^[1]

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1. Department of Physics, University of California, Berkeley, California 94720 (United States)

Numerical studies, from variational calculation to exact diagonalization, all indicate that the quasiparticle generated by introducing one hole into a two-dimensional quantum antiferromagnet has the same nature as a string state in the {ital t}-{ital J}{sub {ital z}} model. Based on this observation, we attempt to visualize the quasiparticle formation and subsequent coherent propagation at low energy by studying the generalized {ital t}-{ital J}{sub {ital z}}-{ital J}{sub {perpendicular}} model in which we first diagonalize the {ital t}-{ital J}{sub {ital z}} model and then perform a {ital degenerate} perturbation in {ital J}{sub {perpendicular}}. We construct the quasiparticle state and derive an effective Hamiltonian describing the coherent propagation of the quasiparticle and its interaction with the spin wave excitations in the presence of the N{acute e}el order. We expect that qualitative properties of the quasiparticle remain intact when analytically continuing {ital J}{sub {perpendicular}} from the anisotropic {ital J}{sub {perpendicular}}{lt}{ital J}{sub {ital z}} to the isotropic {ital J}{sub {perpendicular}}={ital J}{sub {ital z}} limit, despite the fact that the spin wave excitations change from gapful to gapless. Extrapolating to {ital J}{sub {perpendicular}}={ital J}{sub {ital z}}, our quasiparticle dispersion and spectral weight compare well with the exact numerical results for small clusters. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 434524
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 2 Vol. 53; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANTIFERROMAGNETISM
CUPRATES
ELECTRON CORRELATION
HIGH-TC SUPERCONDUCTORS
HOLES
MATHEMATICAL MODELS
QUASI PARTICLES
SUPERCONDUCTIVITY
TRANSPORT THEORY