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arXiv · 0808.3491

Spin-Orbit Integrated Ground State and Magnetic Anisotropy in Sr$_2$IrO$_4$

Hosub Jin·Hogyun Jeong·Taisuke Ozaki·Jaejun Yu
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Abstract

We present a microscopic model for the anisotropic exchange interactions in Sr$_{2}$IrO$_{4}$. A direct construction of Wannier functions from first-principles calculations proves the $j_{\mathrm{eff}}$=1/2 character of the spin-orbit integrated states at the Fermi level. An effective $j_{\mathrm{eff}}$-spin Hamiltonian explains the observed weak ferromagnetism and anisotropy of antiferromagnetically ordered magnetic state, which arise naturally from the $j_{\mathrm{eff}}$=1/2 state with a rotation of IrO$_{6}$ octahedra. It is suggested that Sr$_{2}$IrO$_{4}$ is a unique class of materials with effective exchange interactions in the spin-orbital Hilbert space.

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Hosub Jin, Hogyun Jeong, Taisuke Ozaki, Jaejun Yu. 2009-07-24. Spin-Orbit Integrated Ground State and Magnetic Anisotropy in Sr$_2$IrO$_4$. https://doi.org/10.1103/physrevb.80.075112

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