Ferrimagnetism of dilute Ising antiferromagnets

TL;DR

This paper demonstrates that certain dilute Ising antiferromagnets can exhibit ferrimagnetic order due to lattice imbalance and percolation effects, challenging the typical antiferromagnetic expectation.

Contribution

It reveals that lattice imbalance and percolation clusters induce ferrimagnetism in dilute Ising antiferromagnets, supported by experimental evidence on Fe_pZn_{1-p}F_2.

Findings

Ferrimagnetism arises from lattice imbalance and percolation effects.

Experimental evidence from Fe_pZn_{1-p}F_2 supports theoretical predictions.

Ferrimagnetic behavior is inherent to bcc lattice structures.

Abstract

It is shown that nearest-neighbor antiferromagnetic interactions of identical Ising spins on imbalanced bipartite lattice and imbalanced bipartite hierarchical fractal result in ferrimagnetic order instead of antiferromagnetic one. On some crystal lattices dilute Ising antiferromagnets may also become ferrimagnets due to the imbalanced nature of the magnetic percolation cluster when it coexists with the percolation cluster of vacancies. As evidenced by the existing experiments on $Fe_pZn_{1-p}F_2$, such ferrimagnetism is inherent property of bcc lattice so thermodynamics of these compounds at low $p$ can be similar to that of antiferromagnet on imbalanced hierarchical fractal.