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arXiv · 1311.3439

Helical multiferroics for electric field controlled quantum information processing

M. Azimi·L. Chotorlishvili·S. K. Mishra·S. Greschner·T. Vekua·J. Berakdar
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Abstract

Magnetoelectric coupling in helical multiferroics allows to steer spin order with electric fields. Here we show theoretically that in a helical multiferroic chain quantum information processing as well as quantum phases are highly sensitive to electric (E) field. Applying E-field, the quantum state transfer fidelity can be increased and made directionally dependent. We also show that E field transforms the spin-density-wave/nematic or multipolar phases of frustrated ferromagnetic spin-1/2 chain in chiral phase with a strong magnetoelectric coupling. We find sharp reorganization of the entanglement spectrum as well as a large enhancement of fidelity susceptibility at Ising quantum phase transition from nematic to chiral states driven by electric field. These findings point to a new tool for quantum information with low power consumption.

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M. Azimi, L. Chotorlishvili, S. K. Mishra, S. Greschner, T. Vekua, J. Berakdar. 2013-11-14. Helical multiferroics for electric field controlled quantum information processing. https://doi.org/10.1103/physrevb.89.024424

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