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arXiv · 1802.01236

Studies on the high-temperature ferroelectric transition of multiferroic hexagonal manganite RMnO3

Hasung Sim·Jaehong Jeong·Haeri Kim·S-W Cheong·Je-Geun Park
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Abstract

Hexagonal manganites are multiferroic materials with two highly-dissimilar phase transitions: a ferroelectric transition (from P63/mmc to P63cm) at a temperature higher than 1000 K and an antiferromagnetic transition at TN=65 - 130 K. Despite its critical relevance to the intriguing ferroelectric domain physics, the details of the ferroelectric transition are yet not well known to date primarily because of the ultra-high transition temperature. Using high-temperature X-ray diffraction experiments, we show that the ferroelectric transition is a single transition of abrupt order and R-Op displacement is the primary order parameter. This structural transition is then simultaneously accompanied by MnO5 tilting and the subsequent development of electric polarization.

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Hasung Sim, Jaehong Jeong, Haeri Kim, S-W Cheong, Je-Geun Park. 2018-02-05. Studies on the high-temperature ferroelectric transition of multiferroic hexagonal manganite RMnO3. https://doi.org/10.1088/1361-648x/aaab87

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