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arXiv · 0706.3066

Dielectric microscopy with submillimeter resolution

Nathan S. Greeney·John A. Scales
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Abstract

In analogy with optical near-field scanning methods, we use tapered dielectric waveguides as probes for a millimeter wave vector network analyzer. By scanning thin samples between two such probes we are able to map the spatially varying dielectric properties of materials with sub-wavelength resolution; using a 150 GHz probe in transmision mode we see spatial resolution of around 500 microns. We have applied this method to a variety of highly heterogeneous materials. Here we show dielectric maps of granite and oil shale.

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Nathan S. Greeney, John A. Scales. 2007-06-20. Dielectric microscopy with submillimeter resolution. https://doi.org/10.1063/1.2818674

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