"This project aims to design the first ever prototype of a plasmonic microscope for in vivo bio imaging. The principle behind the prototype consists in deep sub-wavelength focusing and raster scanning of multiple points to achieve imaging. On the one hand, using surface plasmons excitation for microscopy instead of light offers the advantage of ultra short plasmonic wavelengths (down to 100 nm) for visible light frequencies, enabling a plasmonic diffraction limit of 50 nm which sets the resolution of the microscopy. On the other hand, in this ultra short wavelength regime surface plasmons suffer losses, limiting the propagation length of plasmon waves. Losses limit the image size (field of view) to no more than 10 by 10 resolution points, a size which is completely insufficient for biological samples. The main scientific challenge of this proposal is to surpass the plasmonic losses which constitute a limitation for microscopy and most plasmonic applications. While previous attempts were based on reducing the losses (succeeded up by a factor of two), we propose a scheme that is not sensitive to these losses. The scheme consists in a ""network"" of periodic plasmonic repeaters that regenerate the lossy signals, similarly to the standard method used for distributing cellular phones and TV/radio signals over long distances. In particular, we will use a Spatial Light Modulator (SLM) to create and scan multiple plasmonic foci in parallel. The image is acquired via raster scanning of all the plasmonic foci in parallel, yielding an image size limited only by the extension of the network, namely the number of pixels in the SLM. Moreover, this scheme also reduces the scanning time by up to two orders of magnitudes, making it suitable for in-vivo measurements.
In conclusion, we propose a technological advancement for microscopy based on a novel scheme that can harvest the short plasmonic wavelengths for microscopy without compromising any other relevant parameters."
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