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arXiv · 0906.2733

Magnetically Hidden Order of Kramers Doublets in $d^1$ Systems: Sr$_2$VO$_4$

George Jackeli·Giniyat Khaliullin
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Abstract

We formulate and study an effective Hamiltonian for low-energy Kramers doublets of $d^1$-ions on a square lattice. We find that the system exhibits a magnetically hidden order in which the expectation values of the local spin and orbital moments both vanish. The order parameter responsible for a time-reversal symmetry breaking has a composite nature and is a spin-orbital analog of a magnetic octupole. We argue that such a hidden order is realized in the layered perovskite Sr$_2$VO$_4$.

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George Jackeli, Giniyat Khaliullin. 2009-08-09. Magnetically Hidden Order of Kramers Doublets in $d^1$ Systems: Sr$_2$VO$_4$. https://doi.org/10.1103/physrevlett.103.067205

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