Magnetic order in a spin-1/2 interpolating kagome-square Heisenberg antiferromagnet

TL;DR

This paper investigates the magnetic order in a spin-1/2 Heisenberg antiferromagnet model that interpolates between kagome and square lattices using the coupled cluster method, providing insights into its zero-temperature phase diagram.

Contribution

It applies the coupled cluster method to a novel interpolating model, revealing detailed magnetic ordering and phase transitions at zero temperature.

Findings

Results for the kagome HAF limit are among the best available.

The phase diagram shows distinct magnetic phases depending on bond parameters.

The model bridges kagome and square lattice antiferromagnets, elucidating their magnetic properties.

Abstract

The coupled cluster method is applied to a spin-half model at zero temperature ($T=0$), which interpolates between Heisenberg antiferromagnets (HAF's) on a kagome and a square lattice. With respect to an underlying triangular lattice the strengths of the Heisenberg bonds joining the nearest-neighbor (NN) kagome sites are $J_{1} \geq 0$ along two of the equivalent directions and $J_{2} \geq 0$ along the third. Sites connected by $J_{2}$ bonds are themselves connected to the missing NN non-kagome sites of the triangular lattice by bonds of strength $J_{1}' \geq 0$. When $J_{1}'=J_{1}$ and $J_{2}=0$ the model reduces to the square-lattice HAF. The magnetic ordering of the system is investigated and its $T=0$ phase diagram discussed. Results for the kagome HAF limit are among the best available.