Layered frustrated antiferromagnetic Heisenberg spin model: role of inplane frustration and interlayer coupling

TL;DR

This study uses exact diagonalization to explore how in-plane frustration and interlayer coupling influence magnetic order in a layered $J_1$-$J_2$ antiferromagnetic Heisenberg model, revealing phase transitions and state narrowing.

Contribution

It provides a detailed analysis of the layered $J_1$-$J_2$ model with interlayer coupling using exact diagonalization, highlighting the effects on magnetic phases and quantum disordered states.

Findings

Interlayer coupling induces long-range magnetic order.

Quantum disordered state interval narrows with increased interlayer coupling.

System transitions between Néel and collinear ordered states.

Abstract

We present an exact diagonalization study on layered $J_{1}-J_{2}$ antiferromagnetic Heisenberg spin model to examine the role of frustration induced by inplane next-nearest neighbor coupling $J_{2}$, in presence of interlayer antiferromagnetic coupling $J_{\perp}$. A finite lattice of 24 spins in layered geometry of $(4\times 3)\oplus (4\times 3)$ is considered and the resulting Hamiltonian matrix diagonalized using Davidson iterative algorithm to obtain the ground and a few low-lying excited states. The lattice size ($24$ spins with Hilbert space dimensionality of $2704156$ in $S_{z}^{tot}=0$ subspace) has been kept relatively small because of the large number of runs required to sample $J_{1}-J_{2}-J_{\perp}$ parameter space. Quantities like spin-gap, Shannon entropy, spin-spin correlation, static spin structure-factor, magnetic specific-heat and magnetic susceptibility are calculated for various values of spin-spin coupling parameters. With increase in interlayer coupling, the system is driven to states with long range order and the interval of quantum paramagnetically disordered state, sandwiched between N\'{e}el and collinear ordered states, narrows on the scale of inplane frustration parameter.