Fig. 2: Characterization of room-temperature ferroelectricity in strained SrTiO3 membranes.
From: Strain-induced room-temperature ferroelectricity in SrTiO3 membranes
a Schematic illustrating the strain apparatus, wherein the SrTiO3 membrane and polyimide sheet are stretched and fixed to a rigid substrate to maintain their strain state, with the ordered array of gold markers used for strain calibration. Grazing incidence X-ray diffraction (GIXRD) results measured along b [100] strain direction and c [010] direction which was fixed to the unstrained state. d Comparison of GIXRD strain and the optically measured nominal strain. Error bars within the size of the marker represent the standard deviation. Piezoresponse force microscopy (PFM) amplitude e and phase f measured from unstrained membranes exhibit weak piezoresponse, indicating the absence of room-temperature ferroelectricity, illustrated in schematic g. PFM amplitude h and phase i measured from 2.0% uniaxially strained membranes exhibit room-temperature ferroelectricity with the notable 180° domain structure, illustrated in schematic j. The scale bar is 1 µm.
