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arXiv · 0906.0324

Magnetic digital flop of ferroelectric domain with fixed spin chirality in a triangular lattice helimagnet

S. Seki·H. Murakawa·Y. Onose·Y. Tokura
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Abstract

Ferroelectric properties in magnetic fields of varying magnitude and direction have been investigated for a triangular-lattice helimagnet CuFe1-xGaxO2 (x=0.035). The magnetoelectric phase diagrams were deduced for magnetic fields along [001], [110], and [1-10] direction, and the in-plane magnetic field was found to induce the rearrangement of six possible multiferroic domains. Upon every 60-degree rotation of in-plane magnetic field around the c-axis, unique 120-degree flop of electric polarization occurs as a result of the switch of helical magnetic q-vector. The chirality of spin helix is always conserved upon the q-flop. The possible origin is discussed in the light of the stable structure of multiferroic domain wall.

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S. Seki, H. Murakawa, Y. Onose, Y. Tokura. 2009-11-12. Magnetic digital flop of ferroelectric domain with fixed spin chirality in a triangular lattice helimagnet. https://doi.org/10.1103/physrevlett.103.237601

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