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arXiv · 1101.4284

Unconventional Multiferroicity in Cupric Oxide

Pierre Toledano·Naemi Leo·Dmitry D. Khalyavin·Laurent C. Chapon·Tim Hoffmann·Dennis Meier·Manfred Fiebig
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Abstract

The magnetic phase transitions reported below 230 K in cupric oxide are analyzed theoretically at the macroscopic and microscopic levels. The incommensurate multiferroic and lock-in commensurate phases are shown to realize an inverted sequence of symmetry-breaking mechanisms with respect to the usual sequence occurring in low temperature multiferroic compounds. The higher temperature spin-spiral phase results from coupled order-parameters which decouple at the lock-in transition to the commensurate ground state phase. Expressing the order-parameters in function of the magnetic spins allows determining the symmetries and magnetic structures of the equilibrium phases and the microscopic interactions which give rise to the polarization.

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Pierre Toledano, Naemi Leo, Dmitry D. Khalyavin, Laurent C. Chapon, Tim Hoffmann, Dennis Meier, Manfred Fiebig. 2011-01-22. Unconventional Multiferroicity in Cupric Oxide. https://arxiv.org/abs/1101.4284

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