Photo-Controlled Ferroelectric-Based Nanoactuators

Abstract

Finding a feasible principle for a future generation of nanooptomechanical systems is a matter of intensive research, because it may provide new device prospects for optoelectronics and nanomanipulation techniques. Here we show that the strain of a ferroelectric crystal can be manipulated to achieve macroscopic, stable, and reproducible dimensional changes using illumination with photon energy below the material bandgap. The photoresponse can be activated without direct light incidence on the actuation area, because the cooperative nature of the phenomenon extends the photoinduced strain to the whole material. These results may be useful for developing the next generation of high-efficiency photocontrolled ferroelectric devices.

Photostrictive Effect: Characterization Techniques, Materials, and Applications

“…recently presented several interesting studies on the photoinduced structural evolution of BaTiO 3 single crystals by using advanced characterization techniques. [ 64 ] Through employing atomic force microscopy, they observed an obvious surface height change in BaTiO 3 crystal when irradiated by 532 nm light. [ 64c ] Besides, the height change was linearly dependent on the light power ( Figure a), and a maximum photoinduced strain of 0.04% was obtained under the light power of 60 mW, which is comparable with that reported in PLZT.…”

“…[ 64 ] Through employing atomic force microscopy, they observed an obvious surface height change in BaTiO 3 crystal when irradiated by 532 nm light. [ 64c ] Besides, the height change was linearly dependent on the light power ( Figure a), and a maximum photoinduced strain of 0.04% was obtained under the light power of 60 mW, which is comparable with that reported in PLZT. As regards the physical origin of the large photostrictive response in BaTiO 3 , the photovoltaic effect, generally acknowledged as the origin of the photostriction in ferroelectrics, was discarded due to the insufficient photon energy of the 532 nm light source in comparison with the bandgap (3.2 eV) of BaTiO 3 .…”

“…In addition, they observed the light‐induced domain wall motion of BaTiO 3 at local scale by using in situ confocal Raman microscope. [ 64a ] The Raman mapping images (Figure 15b) clearly show the domain wall motion by adjusting the angles of the polarized light. Both the c ‐domains (blue) and b ‐domains (green) move along the x ‐axis, which implies a modification of the structure.…”

“…They further observed the light‐induced structural changes at macroscopic scale by employing the high‐resolution synchrotron XRD techniques. [ 64b ] The XRD patterns (Figure 15c) were collected at a synchrotron light‐irradiated multidomain zone of the (100)‐orientated BaTiO 3 crystal. The a ‐plane contributions of b ‐domains and c ‐domains are evidenced by the splitting of ( h 00) peaks into ( h 00), (0 h 0), and (00 h ) degenerate reflections.…”

“…Reproduced with permission. [ 64c ] Copyright 2019, American Chemical Society. b) Polarized light induced domain wall motion of BaTiO 3 crystal revealed by Raman mapping images (scale bar 1 µm).…”