Nanometric magnetic and piezo domain studies on multiferroic BTO-CFO based-nanostructures

Multiferroic BTO-CFO was chosen for this study to understand multifunctional properties at the nanometer scale. The bulk pellet and nano-structured thin films of these compounds were synthesized. The films fabricated by pulsed laser deposition (PLD) technique, using the same material as target, were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). About 100-nm-thick films showed different nanostructures of BTO-CFO which PLD grown at deposited in same conditions on various substrates like silicon, quartz, and strontium titanate (STO). Morphological studies revealed the presence of about ~ 50 nm sized nanostructured pillars. The multiferroic properties in these nanocomposite films were characterized using multimode scanning probe microscopy (SPM). Magnetic force microscopy studies revealed the distribution of magnetic domains with a diameter of < 50 nm range in BTO matrix while using a silicon substrate. Piezo force microscopy available as a special SPM mode provided the evidence on the presence of piezoelectric domain and their behavior. Spatially, varying piezoelectric response was observed. Among the films with composite architectures, nanostructure BTO-CFO film on STO yielded maximum piezo response. Domain interfaces in both cases involving thin films and pellets are bestowed with special features. © 2002-2012 IEEE.