Dynamically actuated soft heliconical architecture via frequency of electric fields

Abstract

Dynamic electric field frequency actuated helical and spiral structures enable a plethora of attributes for advanced photonics and engineering in the contemporary era. Nevertheless, leveraging the frequency responsiveness of adaptive devices and systems within a broad dynamic range and maintaining restrained high-frequency induced heating remain challenging. Herein, we establish a frequency-actuated heliconical soft architecture that is quite distinct from that of common frequency-responsive soft materials. We achieve reversible modulation of the photonic bandgap in a wide spectral range by delicately coupling the frequency-dependent thermal effect, field-induced dielectric torque and elastic equilibrium. Furthermore, an information encoder prototype without the aid of complicated algorithm design is established to analogize an information encoding and decoding process with a more convenient and less costly way. A technique for taming and tailoring the distribution of the pitch length is exploited and embodied in a prototype of a spatially controlled soft photonic cavity and laser emission. This work demonstrates a distinct frequency responsiveness in a heliconical soft system, which may not merely inspire the interest in field-assisted bottom-up molecular engineering of soft matter but also facilitate the practicality of adaptive photonics.

Anti-counterfeiting holographic liquid crystal gels with color and pattern control

“…Zheng et al recently reported tunable color-based anti-counterfeiting and light encryption of several cholesteric liquid crystal systems. 49–51 Light-induced dynamic helical transformation of chiral photo-switches in cholesteric liquid crystals can control the color tuning, erasing, reversibility, multistability and viewing angle dependence of pre-recorded patterns. These properties lead to digitally controllable, selectable and extractable multistable reflection states that can be used for anti-counterfeiting or encryption.…”

“…49 Frequency-responsive heliconical LCs have been demonstrated to show reversible modulation of the photonic bandgap over a wide spectral range by delicately combining frequency-dependent thermal effects, field-induced dielectric torque, and elastic equilibrium. 50 They also demonstrated that programmed micro-patterned heliconical structures prepared by local polymer stabilization can be used for anti-counterfeiting applications by controlling the applied electric field to exhibit high color saturation and full color range, including visible light. 51…”

Colorable Light-Scattering Device Based on Polymer-Stabilized Ion-Doped Cholesteric Liquid Crystal and an Electrochromatic Layer

“…The device’s transparent state is highly reliant on the electric field or better vertical alignment, and its light-scattering state must be accompanied by intense dye light absorption. The approach of Bragg reflection band control is mainly based on CLC, − blue-phase LC, − and opal/inverse opal structures, regulating the light reflection band by adjusting the CLC pitch, blue LC lattice structure, and opal structure, respectively. However, these devices did not consider good light-scattering or transparent performance.…”

Untitled

“…Generally, the orientational ordering of LCs can be controlled by different boundary geometries [3] and anchoring conditions [4] , allowing the formation of diverse structures or superstructures, including topological defects (i.e., focal conic domains [5] ). These structures exhibit extraordinary sensitivity to various external stimuli, including light, electric field, heat, force, magnetic field, and so on [6][7][8][9] . Thus, there are many degrees of freedom in the way that the structure is coded and the tunability is devised for the design of soft-matter-based devices with innovative functions.…”