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arXiv · 1612.06049

Evidence of room temperature magnetoelectric properties in {\alpha}-Fe1.6Ga0.4O3 oxide by magnetic field controlled electric properties and electric field controlled magnetism

Abstract

We have stabilized the {\alpha}-Fe1.6Ga0.4O3 (Ga doped {\alpha}-Fe2O3) system in rhombohedral structure. The system has shown magnetically canted ferromagnetic state and ferroelectric properties at room temperature. In first time, we confirm the existence of magneto-electric coupling and multiferro-electric properties at room temperature in the Ga doped {\alpha}-Fe2O3 system based on the experimental observation of magnetic field controlled electric polarization and electric field controlled magnetization. The {\alpha}-Fe2O3 system does not exhibit electric field controlled magnetic exchange bias effect, where as Ga doped {\alpha}-Fe2O3 showed exchange bias shift up to the value of 370 Oe. We have recorded the response of current-voltage characteristics and in-field magnetic relaxation of the system under the simultaneous application of magnetic and electric fields. The magnetization of the system is found highly sensitive to the ON and OFF modes, as well as change of the polarity of external electric field. The system is a new addition in the list of non-traditional magneto-electrics/multi-ferroelectrics so far reported in literature. Such novel materials, where magnetization and electric polarization can be controlled by simultaneous application of magnetic and electric fields, is in the increasing demand for potential applications in the field of next generation magnetic sensor, switching, non-volatile memory and spintronic devices.

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R. N. Bhowmik, Abdul Gaffar Lone. 2016-12-19. Evidence of room temperature magnetoelectric properties in {\alpha}-Fe1.6Ga0.4O3 oxide by magnetic field controlled electric properties and electric field controlled magnetism. https://arxiv.org/abs/1612.06049

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