We introduce a method to investigate the domain stability issue based on piezoresponse microscopy. The switching and back-switching processes of sol–gel derived (Pb0.76Ca0.24)TiO3 thin films were investigated by comparing the local piezoelectric hysteresis loops in continuous mode and pulse mode. It was found that the local hysteresis loops acquired by the pulse mode in shorter pulse width were dominated by the back-switching process while the continuous mode piezoelectric hysteresis loop provides information on the domain switching process.

Low temperature rf sputtering deposition of (Ba, Sr) Ti O 3 thin film with crystallization enhancement by rf power supplied to the substrate J.

SrTiO 3 (STO) thin film was coated on the cladding of a fiber Bragg grating (FBG) by pulsed laser deposition, and the associated temperature sensing properties were tested. The surface of the FBG coating was smooth, uniform, compact and without obvious defects; the structure and properties of the FBG were well protected. Temperature sensing results showed that the sensitivity of the STO coated FBG was about 9.97 pm °C−1 , which is about 28% higher than that of the bare FBG (7.8 pm °C−1 ) before coating. In order to further study the thermal sensing properties of the FBG, a concatenated optical path, two optical paths based on a Michelson interferometer and a Sagnac interferometer, were constructed by using STO coated FBG and another bare FBG as the sensitivity results 9.0 pm °C−1 , 10.5 pm °C−1 and 11.4 pm °C−1 , respectively. Among them, the fiber sensor based on the Sagnac interferometer was more sensitive, which was increased by 46.2%. Moreover, the interference optical path has the advantages of simple structure and good practicality.