Photostrictive Actuators Based on Freestanding Ferroelectric Membranes.

Complex oxides offer a wide range of functional properties, and recent advances in the fabrication of freestanding membranes of these oxides are adding new mechanical degrees of freedom to this already rich functional ecosystem. Here, photoactuation is demonstrated in freestanding thin film resonators of ferroelectric Barium Titanate (BaTiO) and paraelectric Strontium Titanate (SrTiO). The free-standing films, transferred onto perforated supports, act as nano-drums, oscillating at their natural resonance frequency when illuminated by a frequency-modulated laser.

Enhanced Thermoelectric Properties of Misfit BiSrCaCoO: Isovalent Substitutions and Selective Phonon Scattering.

Layered Bi-misfit cobaltates, such as BiSrCoO, are the natural superlattice of an electrically insulating rocksalt (RS) type BiSrO layer and electrically conducting CoO layer, stacked along the crystallographic c-axis. RS and CoO layers are related through charge compensation reactions (or charge transfer). Therefore, thermoelectric transport properties are affected when doping or substitution is carried out in the RS layer.