1 research outputs found
A Local Nanofiber-Optic Ear
The development of
acoustic sensors that are compact, have simple
read-out mechanisms, and have geometries that enable them to be inserted/embedded
deep in materials is of great interest for acoustic-based imaging
technologies and novel analytical instruments. Fiber-optic-based detectors
are the most logical choice to satisfy these demands, but scaling
down the size to sub-micrometer dimensions and uncovering transduction
mechanisms that can be more robust than interferometric techniques
in dynamic environments has been challenging. In this work, we demonstrate
a non-interference-based acoustic ear that utilizes the movement of
plasmonic nanoparticles embedded in the near field of a nanofiber
optic. The modulated optical signal induced by sound waves can be
read-out through transmission through the nanofiber or by tracking
the scattering of the nanoparticles in the far field. By utilizing
a thin, compressible cladding on the nanofibers, acoustic intensities
of <10<sup>–8</sup> W/m<sup>2</sup> can be detected by the
devices over an interaction area of <4 μm<sup>2</sup>, representing
a measured acoustic power at the sensor of 10<sup>–21</sup> W. With the ability to modify the mechanical properties of the cladding,
change the size of the plasmonic nanoparticle, and alter the guided
wavelength, the performance of this platform is highly tunable and
ideal for compact, deep-body acoustic probes