Neutron Investigations of Multiferroic LuFe1-xMnxO3
ORAL
Abstract
While many new multiferroic materials have surfaced, only BiFeO$_{3}$ has been shown to evince coupling of both order parameters at room temperature. Materials in which the application of an electric field can directly switch the magnetization by 180 degrees have also been elusive. New theoretical predictions suggest that this will be possible in hexagonal LuFeO$_{3}$. Recent measurements of LuFeO$_{3}$ are promising. Bulk LuFeO$_{3}$ crystallizes in the Pbnm space group. However, it can be stabilized in the P6$_{3}$cm space group in thin films. Films are found to be ferroelectric at room temperature with a remanent polarization of 6.5 $\frac{\mu C}{cm^{2}}$along the c-axis and is of a respectable magnitude, evincing long range magnetic order with spins in the plane forming the familiar 120 degree structure. At lower temperatures, it was found that the moments begin to cant. Theoretical predictions suggest that this canted moment can be switched with an electric field. Unfortunately, this canting occurs at 130 K. While the recent work in films is exciting, it is important to understand what is intrinsic to the material. Recently, we have been able to stabilize ceramic samples of LuFeO$_{3}$ in the hexagonal form. During this talk we will discuss the magnetic structure of this compound in the bulk. We will also discuss our inelastic neutron scattering results.
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