Supersymmetric mean-field theory of the t-J model
Department of Physics, Hong Kong University of Science and
Technology Clear Water Bay, Hong Kong, PRC
Accepted: 30 July 2000
The supersymmetric formulation of the t-J model is studied in this paper at the mean-field level where the δ-T phase diagram is determined. We found that the slave-fermion–like spiral phase is stable at low doping concentration, and the slave-boson–like d-wave fermionic spin pairing state becomes energetically favourable when . An improvement in free energy using Gutzwiller's method lowers the transition doping concentration to . We also point out the existence of new branches of excitations in the supersymmetric theory.
PACS: 71.10.Fd – Lattice fermion models (Hubbard model, etc.) / 74.20.Mn – Nonconventional mechanisms (spin fluctuations, polarons and bipolarons, resonating valence bond model, anyon mechanism, marginal Fermi liquid, Luttinger liquid, etc.) / 74.25.Dw – Superconductivity phase diagrams
© EDP Sciences, 2000