Programmable Jigsaw Puzzles of Soft Materials Enabled by Pixelated Holographic Surface Reliefs.

Manual intervention in the self-organization of soft matter to obtain a desired superstructure is a complex but significant project. Specifically, optical components made fully or partially from reconfigurable and stimuli-responsive soft materials, referred to as soft photonics, are poised to form versatile platforms in various areas; however, a limited scale, narrow spectral adaptability, and poor stability are still formidable challenges. Herein, a facile way is developed to program the optical jigsaw puzzle of nematic liquid crystals via pixelated holographic surface reliefs, leading to an era of manufacturing for programmable soft materials with tailored functions. Multiscale jigsaw puzzles are established and endowed with unprecedented stability and durability, further sketching a prospective framework toward customized adaptive photonic architectures. This work demonstrates a reliable and efficient approach for directly assembling soft matter, unlocking the long-sought full potential of stimuli-responsive soft systems, and providing opportunities to inspire the next generation of soft photonics and relevant areas.

Dynamically actuated soft heliconical architecture via frequency of electric fields.

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.

Light-Patterned Crystallographic Direction of a Self-Organized 3D Soft Photonic Crystal.

Uniform and patterned orientation of a crystallographic direction of ordered materials is of fundamental significance and of great interest for electronic and photonic applications. However, such orientation control is generally complicated and challenging with regard to inorganic and organic crystalline materials due to the occurrence of uncontrollable dislocations or defects. Achieving uniform lattice orientation in frustrated liquid-crystalline phases, like cubic blue phases, is a formidable task. Taming and tailoring the ordering of such soft, cubic lattices along predetermined or desired directions, and even imparting a prescribed pattern on lattice orientation, are more challenging, due to the entropy-domination attribute of soft matter. Herein, we disclose a facile way to realize designed micropatterning of a crystallographic direction of a soft, cubic liquid-crystal superstructure, exhibiting an alternate uniform and random orientation of the lattice crystallographic direction enabled by a photoalignment technique. Because of the rewritable trait of the photoalignment film, the pattern can be erased and rewritten on-demand by light. Such an oriented soft lattice sensitively responds to various external stimuli such as temperature, electric field, and light irradiation. Furthermore, advanced reflective photonic applications are achieved based on the patterned crystallographic orientation of the cubic blue phase, soft lattice.