- Je-Geun Park: Structure and spin dynamics of multiferroic RMnO3 and BiFeO3
- 3. 7. 2015, 10:30
- lecture room F2, first floor Ke Karlovu 5
- more information
Abstract:
Multiferroic materials that have the coexistence of both magnetic and ferroelectric ground states have drawn significant attention in materials science over the past ten years or so. The underlying origin of this unusual behavior in either naturally occurring materials or artificially synthesized thin films has been a strong enough motivation for material scientists to discover or rediscover new multiferroic materials.
Among a long list of multiferroic materials, hexagonal manganites RMnO3 and BiFeO3 are arguably two most interesting multiferroic materials. In particular, BiFeO3 has been extensively investigated for potential applications by virtue of its magnetic and ferroelectric transitions occurring above room temperature: TN=650 K and TC=1050 K. Moreover, it has a very interesting incommensurate magnetic phase transition with an extremely long period of 650 Å. On the other hand, the hexagonal manganite materials exhibit a natural two-dimensional triangular lattice, which provide an interesting platform to investigate low dimensional magnetism with a supposedly strong coupling to the ferroelectric order parameter.
Over the past few years or so, there have been a multitude of studies done on both compounds. Largely thanks to these extensive studies, we have now come to know extremely details about the physical properties of the two materials. In this talk, I will present our results obtained from high resolution neutron scatteringexperiments on these two fascinating materials.
[1] Seongsu Lee, et al., Nature 451, 805 (2008)
[2] Jaehong Jeong, et al., Phys. Rev. Lett. 108, 077202 (2012)
[3] Joosung Oh, et al., Phys. Rev. Lett. 111, 257202 (2013)
[4] Jaehong Jeong, et al., Phys. Rev. Lett. 113, 107202 (2014)
[5] [Review] Je-Geun Park, et al., J. Phys.: Condens. Matter 26, 433202 (2014)