Nature provides well‐engineered and evolutionary optimized examples of brilliant structural colors in animals and plants. Morpho butterflies are among the well‐known species possessing iridescent bright blue coloration due to multiple optical effects generated by the complex structuration of the wing scales. Such surprising solution can be replicated to fabricate efficient devices. Maybe even more interesting, novel approaches can be developed to combine wings with synthetic smart materials to achieve complex structures responsive to external stimuli. This study demonstrates the proof of concept of an innovative biotic–abiotic hybrid smart structure made by the integration of a butterfly wing with thermoresponsive liquid crystalline elastomers, and their capability to actuate the mechanical action of the wing, thus controlling its spectral response. Exploiting two fabrication strategies, it is demonstrated how different mechanisms of color tuning can be achieved by temperature control. In addition, due to the thermally induced mechanical deformation of the elastomer and superhydrophobic properties of the wing, a potential self‐cleaning behavior of the bilayer material is demonstrated.

Photopolymerization of customized materials became a well-established technique for micro-and nanofabrication of photonic structures, and their optical properties as the refractive index should be precisely tailored to design specific photonic features. For this purpose, the refractive index determination in macroscopic samples is not exhaustive, and an in situ characterization is thus necessary at both the macro-and microscale to point out how different polymerization processes differently modulate the optical properties. In particular, we focus our attention on liquid crystalline networks (LCNs) that have been studied as birefringent materials whose tunable response is of interest for applications in different fields such as in robotics, biomedicine, and photonics. By tuning the molecular composition of LCN mixtures, e.g., modifying the cross-linker and dye amount inside the polymer network, the refractive index and the optical anisotropy of microscopic and macroscopic samples have been engineered and measured by a refractometer method under temperature variation or light actuation stimuli. Monitoring the refractive index at different length scales showed that two-photon polymerization increases the birefringence in microscopic structures, and the maximum variation of the optical anisotropy is achieved by a remote laser light stimulus.

Enhancing the resolution of 3D patterning techniques in functional soft polymers enlarges the application areas of responsive shape‐changing materials, for tunable nanophotonics and nanorobotics. Thanks to the recent advances of polymer science, the palette of available materials for nanomanufacturing is becoming wider and wider—although the comprehension of their polymerization process by two‐photon polymerization is still incomplete. In this work, both shrinking of the minimal polymerizable unit and a significant improvement of the mechanical stability of microstructured soft polymers, in particular of liquid crystalline networks, are demonstrated. To this aim, temperature control enhances the resolution and reduces the swelling of the polymerized structures, thus avoiding deviations of the final structure from the intended design. This fine control on the nanoscale features enables the use of soft responsive materials not only for bulky microelements, but also for high‐resolution structures with more complex design.

Photonic crystals owe their multitude of optical properties to the way their structure creates interference effects. It is therefore possible to influence the photonic response by acting on their physical structure. In this article, tunable photonic crystals made by elastic polymers that respond to their environment are explored, in particular with a physical deformation under temperature variation. This creates a feedback process in which the photonic response depends on its physical structure, which itself is influenced by the environmental changes. By using a multi‐photon polymerization process specifically optimized for soft responsive polymers such as Liquid Crystalline Networks, highly resolved, reproducible, and mechanically self‐standing photonic crystals are fabricated. The physical structure of the 3D woodpile can be tuned by an external temperature variation creating a reversible spectral tuning of 50 nm in the telecom wavelength range. By comparing these results with finite element calculations and temperature induced shape‐change, it is confirmed that the observed tuning is due to an elastic deformation of the structure. The achieved nanometric patterning of tunable anisotropic photonic materials will further foster the development of reconfigurable photonic crystals with point defects acting as tunable resonant cavities and, more in general, of 4D nanostructures.