Spin gap in doped dimerized chain near half-filling
Journal
Physica B: Condensed Matter
Journal Volume
334
Journal Issue
3-4
Pages
451-455
Date Issued
2003
Author(s)
Jiang, X.
Abstract
By applying a variational approximation to the bosonized Hamiltonian, the spin gap in a doped spontaneously dimerized spin chain is investigated analytically based on the tJJ′ model in one dimension in the region of small hole doping and small-J limit. It is found that the spin gap is easily destroyed by hole doping. There is a critical value of the hole density at which the system undergoes a continuous crossover from a frustrated quantum liquid with a spin gap to a Tomonaga-Luttinger liquid without a spin gap. Our results are consistent with that from the exact diagonalization method and can also explain some experimental behaviors in the high-Tc materials. © 2003 Elsevier Science B.V. All rights reserved.
SDGs
Type
journal article