Circularly Polarized Light-driven Liquid Crystal Elastomer Actuators

Photo-responsive liquid crystal elastomer (LCE) actuator is of paramount significance for emerging applications in soft robotics, biomimetic devices, and adaptive optical devices. However, to achieve circularly polarized light-driven LCE actuator, which can provide an additional degree of freedom of light in the control method, is still a challenge. Herein, a circularly polarized light-driven LCE actuator is demonstrated. The actuator is fabricated by bonding a cholesteric liquid crystal (CLC) film, which is capable of selectively reflecting and transmitting circularly polarized light, with a photothermal agent doped LCE film in splay configuration as a bilayer structure. An electrically controlled optical system with a fast switching ability of circularly polarized light's handedness has been developed to study the circularly polarized light-response bending property of the proposed actuator under various periodic driven voltage schemes. A crawler driven by circularly polarized light based on CLC-LCE actuator is demonstrated experimentally with different moving modes. The application of circularly polarized light in the LCE actuator driving provides an additional controlling degree of freedom for photo-responsive LCE actuators besides the wavelength, spatial distribution, and linear polarization of light, showing wide application prospects in soft robotics, biomimetic technologies, and adaptive optical devices.