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Triplet superconductivity in a one-dimensional ferromagnetic t-J model

G. I. Japaridze·E. Müller-Hartmann
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Abstract

In this paper we study the ground state phase diagram of a one-dimensional $t-U-J$ model, at half-filling. In the large-bandwidth limit and for ferromagnetic exchange with easy-plane anisotropy, a phase with gapless charge and massive spin excitations, characterized by the coexistence of triplet superconducting ($TS$) and spin density wave ($SDW^{z}$) instabilities is realized in the ground state. With reduction of the bandwidth, a transition into an insulating phase showing properties of the spin-1/2 XY model takes place. In the case of weakly anisotropic antiferromagnetic exchange the system shows a long range dimerized (Peierls) ordering in the ground state. The complete weak-coupling phase diagram of the model, including effects of the on-site Hubbard interaction, is obtained.

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G. I. Japaridze, E. Müller-Hartmann. 1999-07-27. Triplet superconductivity in a one-dimensional ferromagnetic t-J model. https://doi.org/10.1103/physrevb.61.9019

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