Field-induced reentrant novel phase and a ferroelectric-magnetic order coupling in HoMnO3.
نویسندگان
چکیده
A reentrant novel phase is observed in the hexagonal ferroelectric HoMnO3 in the presence of magnetic fields in the temperature range defined by a plateau of the dielectric constant anomaly. The plateau evolves with fields from a narrow dielectric peak at the Mn-spin rotation transition at 32.8 K in zero field. The anomaly appears both as a function of temperature and as a function of magnetic field without detectable hysteresis. This is attributed to the indirect coupling between the ferroelectric (FE) and antiferromagnetic (AFM) orders, arising from an FE-AFM domain wall effect.
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عنوان ژورنال:
- Physical review letters
دوره 92 8 شماره
صفحات -
تاریخ انتشار 2004