Structural proteins from naturally occurring materials are an inspiring template for material design and synthesis at multiple scales. The ability to control the assembly and conformation of such materials offers the opportunity to define fabrication approaches that recapitulate the dimensional hierarchy and structure-function relationships found in nature. A simple and versatile directed assembly method of silk fibroin, which allows the design of structures across multiple dimensional scales by generating and tuning structural color in large-scale, macro defect-free colloidally assembled 3D nanostructures in the form of silk inverse opals (SIOs) is reported. This approach effectively combines bottom-up and top-down techniques to obtain control on the nanoscale (through silk conformational changes), microscale (through patterning), and macroscale (through colloidal assembly), ultimately resulting in a controllable photonic lattice with predefined spectral behavior, with a resulting palette spanning almost the entire visible range. As a demonstration of the approach, examples of "multispectral" SIOs, paired with theoretical calculations and analysis of their response as a function of changes of lattice constants and refractive index contrast are illustrated.

Natural systems display sophisticated control of light-matter interactions at multiple length scales for light harvesting, manipulation, and management, through elaborate photonic architectures and responsive material formats. Here, we combine programmable photonic function with elastomeric material composites to generate optomechanical actuators that display controllable and tunable actuation as well as complex deformation in response to simple light illumination. The ability to topographically control photonic bandgaps allows programmable actuation of the elastomeric substrate in response to illumination. Complex three-dimensional configurations, programmable motion patterns, and phototropic movement where the material moves in response to the motion of a light source are presented. A “photonic sunflower” demonstrator device consisting of a light-tracking solar cell is also illustrated to demonstrate the utility of the material composite. The strategy presented here provides new opportunities for the future development of intelligent optomechanical systems that move with light on demand.

We present a systematic comparison between guided modes supported by slab waveguides and Bloch Surface Waves (BSWs) propagating at the surface of truncated periodic multilayers. We show that, contrary to common belief, the best surface field enhancement achievable for guided modes in a slab waveguide is comparable to that observed for BSWs. At the same time, we demonstrate that, if one is interested in maximizing the electromagnetic energy density at a generic point of a dielectric planar structure, BSWs are often preferable to modes in which light is confined uniquely by total internal reflection. Since these results are wavelength independent and have been obtained by considering a very wide range of refractive indices of the structure constituent materials, we believe they can prove helpful in the design of future structures for the control and the enhancement of the light-matter interaction.

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In this work, we experimentally demonstrate confined modes in a Bloch surface wave (BSW) ring resonator. We fabricate and characterize a ring resonator with a radius R = 105 μm on a truncated periodic porous silicon multilayer. We show resonant modes around 1.5 μm with quality factors exceeding 103. These results suggest that this platform is promising to develop integrated optical resonators based on BSWs.

In article number https://doi.org/10.1002/adma.201702769, Fiorenzo G. Omenetto and co‐workers demonstrate a new kind of amorphous silk‐based large‐scale inverse opal by an approach that effectively combines bottom‐up and top‐down techniques to obtain control on the nanoscale, microscale, and macroscale, resulting in a controllable photonic lattice and a resulting palette spanning almost the entire visible range. Thus, sub‐millimeter, multispectral patterns are defined.

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In recent years, outreach activities have acquired great importance among the three university missions for the involvement of the non-expert community. In this context, the "Physics4Teenagers" outreach group of the Physics Department of Pavia University, in Northern Italy, designed the "PER me si va ne la fisica recente" experience. In physics promotion, our major target are usually high school students with a particular focus on the choice of their future studies. With this in mind, we decided to exploit a new format: the educational escape room. Based on the success of recreational escape rooms, this format has acquired great visibility in the last decades, combining entertainment with learning goals. Besides, it allows for the development of soft skills such as collaboration and critical thinking through hands-on activities. We created a journey through the history of particle physics from the atomic theory of Democritus to the discovery of the Higgs boson, which completes the Standard Model. Furthermore, we pushed the boundaries of our map towards the questions that remain unsolved in this theory, such as the problem of dark matter, neutrino masses and oscillations, and unification of forces. At the end of the escape room, we asked the participants for feedback and suggestions through a satisfaction questionnaire. The good results in both occasions confirm the suitability of the format and the effectiveness of the friendly and informal attitude.