Magnetic properties, Lyapunov exponent and superstability of the spin-1/2 Ising-Heisenberg model on diamond chain

TL;DR

This paper provides exact solutions for the magnetic properties and Lyapunov exponents of the spin-1/2 Ising-Heisenberg diamond chain model, revealing magnetization plateaus, phase behavior, and supercritical points at low temperatures.

Contribution

It introduces the first identification of supercritical points in the model at zero magnetic field and low temperature, with detailed analysis of Lyapunov exponents and phase properties.

Findings

Magnetization plateau at one third saturation in antiferromagnetic case

Existence of two ferrimagnetic and one paramagnetic phases at low temperatures

Maximal Lyapunov exponent exhibits plateau and different behaviors in ferrimagnetic phases

Abstract

The exactly solvable spin-1/2 Ising-Heisenberg model on diamond chain has been considered. We have found the exact results for the magnetization by using recursion relation method. The existence of the magnetization plateau has been observed at one third of the saturation magnetization in the antiferromagnetic case. Some ground-state properties of the model are examined. At low temperatures, the system has two ferrimagnetic (FRI1 and FRI2) phases and one paramagnetic (PRM) phase. Lyapunov exponents for the various values of the exchange parameters and temperatures have been analyzed. It have also been shown that the maximal Lyapunov exponent exhibits plateau. Lyapunov exponents exhibit different behavior for two ferrimagnetic phases. We have found the existence of the supercritical point for the multi-dimensional rational mapping of the spin-1/2 Ising-Heisenberg model on diamond chain for the first time at absence of the external magnetic field and $T \rightarrow 0$ in the antiferromagnetic case.