Parametric Study on Beam Deflection Using Photostrictive Optical Actuators: A Finite Element Modeling Approach

Abstract

The objective of this work is to study the effect of three important parameters such as photostrictive actuator thickness, incident light intensity and convective heat transfer coefficient on a silicon cantilever beam with thin photostrictive optical actuator film surface. The authors have developed a computational method useful for design of systems incorporating thin film photostrictive actuators. The element has been implemented in an in-house finite element code named BAMAFEM. A finite element for static analysis of photostrictive thin films has already been developed and verified with analytical analysis approach of another author. To the best of our knowledge, finite element parametric analysis of the photostrictive thin film has not been extensively studied, if studied at all. Photostrictive materials, such as PLZT, demonstrate significant photostrictive behavior under illumination by high-energy light, which can be considered a superposition of a bulk photovoltaic effect and a converse piezoelectric effect. Photostrictive actuators can directly convert photonic energy to mechanical motion. Photostrictive materials can produce strain as a result of irradiation from high-intensity light. Neither electric lead wires nor electric circuits are required. Thus, photostrictive actuators are relatively immune from electrical interference. They have potential use in numerous MEMS devices. At least from the computational point of view, it would be interesting to investigate the effect of different parameters in the actuation of beam using the thin film photostrictive actuators to develop a finite element model useful for design of numerous MEMS and NANO systems having photostrictive actuators.