Quantum Monte Carlo Simulation of the Trellis Lattice Heisenberg Model for SrCu$_2$O$_3$ and CaV$_2$O$_5$

TL;DR

This paper investigates the spin-1/2 trellis lattice Heisenberg model using quantum Monte Carlo simulations, analyzing how inter-ladder coupling affects the spin gap, dispersion, and susceptibility, with applications to specific materials.

Contribution

It provides new quantum Monte Carlo results for the trellis lattice Heisenberg model and connects theoretical predictions with experimental data on SrCu$_2$O$_3$ and CaV$_2$O$_5$.

Findings

Inter-ladder coupling influences the spin gap and dispersion.

Temperature dependence of susceptibility fits a mean-field scaling.

Experimental data aligns well with the theoretical model.

Abstract

We study the spin-1/2 trellis lattice Heisenberg model, a coupled spin ladder system, both by perturbation around the dimer limit and by quantum Monte Carlo simulations. We discuss the influence of the inter-ladder coupling on the spin gap and the dispersion, and present results for the temperature dependence of the uniform susceptibility. The latter was found to be parameterized well by a mean-field type scaling ansatz. Finally we discuss fits of experimental measurements on SrCu$_2$O$_3$ and CaV$_2$O$_5$ to our results.