Highly directional plasmomechanic stretchable strain sensor

We report asymmetric tuning of nanogap resonance between gold nanoparticles (Au NPs), deposited on anisotropically stretchable polydimethylsiloxane (PDMS) for directional strain sensing. The alternate high and low Young's modulus PDMS line patterns induce anisotropic Poisson's effect (0.45 to 0.61), resulting in direction-dependent plasmon resonance between the Au NPs. For the light polarized perpendicular to the stretching direction, the maximum absorbance peak shift of ~90.85 nm and ~39.13 nm is achieved for 0 = 0° and 0 = 90° direction, respectively.