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arXiv · 1909.08803

A Multiferroic Molecular Magnetic Qubit

Alexander I Johnson·M. Fhokrul Islam·Carlo M. Canali·Mark R Pederson
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Abstract

The chiral $Fe_3O(NC_5H_5)_3(O_2CC_6H_5)_6$ molecular cation, with C$_3$ symmetry, is composed of three six-fold coordinated spin-carrying Fe$^{3+}$ cations that form a perfect equilateral triangle. Experimental reports demonstrating the spin-electric effect in this system also identify the presence of a magnetic uni-axis and suggest that this molecule may be a good candidate for an externally controllable molecular qubit. Here we demonstrate, using standard density-functional methods, that the spin-electric behavior of this molecule could be even more interesting as there are energetically competitive reference states associated with both high and low local spins (S=5/2 vs. S=1/2) on the Fe$^{3+}$ ions. Each of these structures allow for spin-electric ground states. We find that qualitative differences in the broadening of the Fe(2s) and O(1s) core levels and the single-spin anisotropy Hamiltonian may be used to confirm whether the high-spin manifold is lower in energy than the low-spin manifold.

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Alexander I Johnson, M. Fhokrul Islam, Carlo M. Canali, Mark R Pederson. 2019-10-15. A Multiferroic Molecular Magnetic Qubit. https://doi.org/10.1063/1.5127956

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