We demonstrate a dielectric elastomer actuator (DEA) with a high areal strain value of 146% using hybrid electrodes of silver nanowires (AgNWs) and single-walled carbon nanotubes (SWCNTs). The addition of a very small amount of SWCNTs (∼35 ng mm) to a highly resistive AgNW network resulted in a remarkable reduction of the electrode sheet resistance by three orders, increasing the breakdown field by 183% and maximum strain, while maintaining the reduction of optical transmittance within 11%. The DEA based on our transparent and stretchable hybrid electrodes can be easily fabricated by a simple vacuum filtration and transfer process of the electrode film on a pre-strained dielectric elastomer membrane. We expect that our approach will be useful in the future for fabricating stretchable and transparent electrodes in various soft electronic devices.

Wave transport is one of the most interesting topics related to quasicrystals. This is due to the fact that the translational symmetry strongly governs the transport properties of every form of wave. Although quasiperiodic structures with 1-4 or without 1,5-7 disorder have been studied, a clear mechanism for wave transport in three-dimensional quasicrystals including localization is missing 8,9 . To study the intrinsic quasiperiodic e ects on wave transport, the time invariance of the lattice structure and the loss-free condition must be controlled 10,11 . Here, using finite-di erence methods, we study the di usive-like transport and localization of photonic waves in a three-dimensional icosahedral quasicrystal without additional disorder. This result appears at odds with the well-known theory 12 of wave localization (Anderson localization), but we found that in quasicrystals the short mean free path of the photonic waves makes localization possible.The first discovery of a quasicrystal 13 disproved the long-standing conjecture in condensed matter physics that only crystalline materials with translational symmetry could be densely packed and highly ordered. In crystalline materials the waves with wavelengths commensurate with the crystal's periodicity can transmit without scattering loss, leading to ballistic transmission. Disordered materials can be contrasted with ordinary crystals. Because of frequent scattering, wave transport in disordered materials is usually described by random walks leading to diffusive transmission, for example, Ohm's law 14 . Considering the wave nature of electrons, Anderson predicted that if the degree of structural randomness is sufficiently large, the wave interference will result in complete halting of electrons, the so-called Anderson localization 15 , and the transmission coefficient will decrease exponentially with increasing sample thickness 16 . Because of the mixed structural characteristics-for example, the lack of translational symmetry of the disordered media and the highly ordered structure of the ordinary crystals-a critical question has been raised regarding wave transport in quasicrystals, including localization, which has not been thoroughly answered 17 .To the best of our knowledge, this is the first demonstration of the intrinsic localization of photonic waves in a three-dimensional (3D) quasicrystal without additional disorder. Photonic wave localization in a 3D icosahedral quasicrystal is carefully investigated by photonic wave transmission utilizing finite-difference methods. The diffusive transport and localization of photonic waves in the quasicrystal are revealed by widely accepted approaches 18,19 . We characterize the localization phenomena by analysing the spatial and temporal evolution of photonic waves. The localization mechanism is elucidated using the photonic band structures of quasicrystal approximants.An icosahedral quasicrystal structure can be built according to the substitution rules 20 as shown in Fig. 1a-i and further detailed in Supplementary ...

There have been many studies on smart mechanical materials that sensibly deform in response to external stimuli. However, most of the previous studies have focused on structure changes but largely neglected stimuli‐responsive and programmable mechanical properties. Here, we present a novel strategy of mechanical metamaterials, engineered materials with mechanical properties defined by their structure rather than their composition, to design smart materials that change their mechanical properties in response to external stimuli. The present work demonstrates mechanical metamaterials with thermoresponsive and reversible switching between positive and negative Poisson's ratios. In order to realize the thermoresponsive and reversible switching, a thermoresponsive rod with an extremely large thermal expansion coefficient is developed utilizing two‐way shape memory effects. As an application of our metamaterials, we propose soundproofing materials that selectively block sound waves in a specific frequency range depending on temperature.