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S e p t e m b e r 2 4 - 2 6 , 2 0 1 8 | B u d a p e s t , H u n g a r y
OF EXCELLENCE
IN INTERNATIONAL
MEETINGS
YEARS
Magnetic Materials 2018 Materials Science and Nanotechnology | Volume 2
MAGNETISM AND
MAGNETIC MATERIALS
2nd International Conference on
Chenglong Jia, Mater Sci Nanotechnol 2018, Volume 2
ROOM TEMPERATURE SINGLE PHASE
MULTIFERROIC AURIVILLIUS COMPOUND
Chenglong Jia
Lanzhou University, China
Multiferroics (MFs) have attracted great research interest due to
the coexistence of ferroelectric and magnetic ordering, as well as
magnetoelectric (ME) coupling. At present, there is a very limited number of
single-phase MFs known and these are still far from practical applications.
In single-phase MFs, the simultaneous presence of electric and magnetic
dipoles does not guarantee strong (ME) coupling, as the microscopic
mechanisms of ferroelectricity and magnetism are quite different and do
not intrinsically interact with each other. Here we show that in the Aurivillius
system Bi3.25La0.75Ti3-2xNbxFex/2Cox/2O12, the x=0.25 composition is
ferroelectrically and ferromagnetically active at room temperature. A single-
phase structure was supported by XRD, SEM/EDX and neutron diffraction
data. Clear ME couplings were observed in this single-phase material at
room temperature, where the magnetic iron and cobalt ions contribute to
ferroelectric polarization and magnetic moment simultaneously. The results
of structural, electrical and magnetic measurements are supported by first
principle calculations. This discovery of room temperature multiferroic
activity in this system will help to guide the design of room temperature
single-phase MFs with strong ME coupling for sensors and solid-state
memory applications.
Figure.1: Ferroelectric domain switching under magnetic field in BFCT25. (a)
topography and (d) vertical PFM phase at zero magnetic field; (b) topography
and (e) vertical PFM phase at +2000 Oe; (c) topography and (f) vertical PFM
phase at -2000 Oe via FMR.
Chenglong Jia is currently working as a Professor at
Lanzhou University, China. He was the distinguished
visiting fellow of the Royal Academy of Engineering,
UK (2015). He is the Deputy-Director of Key Laborato-
ry for Magnetism and Magnetic Materials of the Min-
istry of Education, Lanzhou University, China. He has
published more than 50 papers in reputed journals
and has been serving as an Editorial Board Member
of repute.
BIOGRAPHY
Recent Publications
1. Li Zheng et al., (2016). Room
temperature magnetoelectric coupling
in intrinsic multiferoic Aurivillius phase
textured ceramics. In Dalton Trans. 45:
14049.
2. Jia C L et al., (2014). Mechanism of
interfacial magnetoelectric coupling in
composite multiferroics. Phys. Rev. B
90: 054423.
3. Jia C L et al., (2007). Microscopic
theory of spin-polarization coupling in
multiferroic transition-metal oxides.
Phys. Rev. B 76: 144424.
4. Jia C L et al., (2006). Bond electronic
polarization induced by spin. Phys.
Rev. B 74: 224444.