Sarkar, Asis and Krupanidhi, SB (2007) Ferroelectric interaction and polarization studies in $BaTiO_3/SrTiO_3$ superlattice. In: Journal of Applied Physics, 101 . pp. 104113-5.
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Received 10 January 2007; accepted 6 March 2007; published online 29 May 2007 Ferroelectric superlattice structures consisting of alternating layers of $BaTiO_3$ and $SrTiO_3$ with variable interlayer thickness were grown on $Pt (111) /TiO_2 /SiO_2/Si (100)$ substrates by pulsed laser deposition. The presence of superlattice reflections in the x-ray diffraction pattern clearly showed the superlattice behavior of the fabricated structures over a range of 6.4–20 nm individual layer thicknesses. Depth profile conducted by secondary ion mass s pectrometry analysis showed a periodic concentration of Ba and Sr throughout the film. Polarization hysteresis and the capacitance-voltage characteristics of these films show clear size dependent ferroelectric characteristics. The spontaneous Ps and remnant Pr polarizations increase gradually with decreasing periodicity, reach a maximum at a finite thickness and then decrease. The competition between the size effect and long-range ferroelectric interaction is suggested as a possible reason for this phenomenon. The temperature dependence of $(P_s)$ and $(P_r)$ shows a single ferroelectric phase transition, and the Curie temperature is estimated to be about 316 K. The curve shows that the ferroelectric superlattice tends to form an artificial material, responding as a single structure with an averaged behavior of both the parent systems.
|Item Type:||Journal Article|
|Additional Information:||Copyright of this article belongs to American Institute of Physics.|
|Department/Centre:||Division of Chemical Sciences > Materials Research Centre|
|Date Deposited:||12 Sep 2007|
|Last Modified:||19 Sep 2010 04:39|
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