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تسجيل مستخدم جديدMagnetic exchange interaction between rare-earth and Mn ions in multiferroic hexagonal manganites
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We report a study of magnetic dynamics in multiferroic hexagonal manganite HoMnO3 by far-infrared spectroscopy. Low-temperature magnetic excitation spectrum of HoMnO3 consists of magnetic-dipole transitions of Ho ions within the crystal-field split J=8 manifold and of the triangular antiferromagnetic resonance of Mn ions. We determine the effective spin Hamiltonian for the Ho ion ground state. The magnetic-field splitting of the Mn antiferromagnetic resonance allows us to measure the magnetic exchange coupling between the rare-earth and Mn ions.
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Multiferroic rare earth manganites attracted recent attention because of the coexistence of different types of magnetic and ferroelectric orders resulting in complex phase diagrams and a wealth of physical phenomena. The coupling and mutual interfere
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