Publication Type
Journal
Journal Name
Physical Review B
Publication Date
Volume
78
Abstract
Using a Monte Carlo (MC) method, we study an effective model for the Fe(II)Fe(III) bimetallic
oxalates. Within a hybrid quantum-classical MC algorithm, the Heisenberg S = 2 and S′ = 5/2
spins on the Fe(II) and Fe(III) sites are updated using a quantum MC loop while the Ising-like
orbital angular momenta on the Fe(II) sites are updated using a single-spin classical MC flip. The
effective field acting on the orbital angular momenta depends on the quantum state of the system.
We find that the mean-field phase diagram for the model is surprisingly robust with respect to
fluctuations. In particular, the region displaying two compensation points shifts and shrinks but
remains finite.
