Magnetic and transport properties of a one dimensional frustrated t-J model for vanadate nanotubes

TL;DR

This paper introduces a one-dimensional frustrated t-J model coupled with a Heisenberg chain to explain ferromagnetic phases in vanadate nanotubes, revealing incommensurate ferrimagnetism and its impact on transport properties.

Contribution

It presents a novel frustrated t-J model coupled with a Heisenberg chain, analyzing magnetic and transport properties in relation to experimental observations.

Findings

The model exhibits incommensurate ferrimagnetic order, not true ferromagnetism.

Transport is suppressed by ferrimagnetic order, contrasting with ferromagnetic Kondo lattice behavior.

Numerical results provide insights into magnetic phases and transport in vanadate nanotubes.

Abstract

We propose a one-dimensional model consisting of a chain with a t-J Hamiltonian coupled to a Heisenberg chain in a frustrated geometry to describe the appearance of the ferromagnetic phase which has been experimentally observed in vanadate nanotubes. This model contains a mechanism of frustration suppressed by doping suggested by L. Krusin-Elbaum, et al. [Nature 431, 672 (2004)]. We study, using numerical techniques in small clusters, the relation between magnetic order and transport properties in the proposed model, and we perform a detailed comparison of the physical properties of this model with those of the ferromagnetic Kondo lattice model. For this comparison, a number of results for the latter model, obtained using the same numerical techniques, will be provided to complement those results already available in the literature. We conclude that it does not appear to be a true ferromagnetic order in the proposed model, but rather an incommensurate ferrimagnetic one, and contrary to what happens in the ferromagnetic Kondo lattice model, electronic transport is somewhat suppressed by this ferrimagnetic order.