Canted spins in orthoferrites RFeO<sub>3</sub>
ORAL
Abstract
The spin-spin exchange interaction as described by the Heisenberg Hamiltonian gives rise to the colinear spin structure. By incorporating the spin-orbit interaction into the Anderson’s theory of superexchange interaction, Moriya derived a new term in the Heisenberg Hamiltonian, the antisymmetric exchange interaction which leads to canted spin structures. The Moriya’s theory provides the microscopic description for the phenomenological theory about the weak ferromagnetism in some antiferromagnetic insulators by Dzyaloshinsky. The Dzyaloshinsky-Moriya interaction (DMI) has been widely applied to account for canted spin structures in a broader range of magnetic materials. In this talk, we will elaborate the weak ferromagnetism in the orthoferrites RFeO3. The canted moment along the c axis in the orthorhombic perovskites with the Pbnm space group was measured by the magnetization in the single crystal samples. The systematic change of the canted moment in the family will be discussed in connection with the structural evolution from LaFeO3 to LuFeO3. The study indicates that the magnetocrystalline anisotropy is responsible for the canted spins instead of the DMI in the orthoferrites.
–
Publication: 1. I. Dzyaloshinsky, J. Phys. Chem. Solids 4, 241 (1958).<br>2. T. Moriya, Phys. Rev. 120, 91 (1960).<br>3. J.-S. Zhou, L. G. Marshall ,† Z.-Y. Li, X. Li , and J.-M. He, Weak ferromagnetism in perovskite oxides, Phys. Rev. B 102, 104420 (2020)<br>
Presenters
-
Jianshi Zhou
University of Texas at Austin, The University of Texas at Austin, University of Texas
Authors
-
Jianshi Zhou
University of Texas at Austin, The University of Texas at Austin, University of Texas