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arXiv · 1002.3632

Mapping local optical densities of states in silicon photonic structures with nanoscale electron spectroscopy

Judy J. Cha·Zongfu Yu·Eric Smith·Martin Couillard·Shanhui Fan·David A. Muller
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Abstract

Relativistic electrons in a structured medium generate radiative losses such as Cherenkov and transition radiation that act as a virtual light source, coupling to the photonic densities of states. The effect is most pronounced when the imaginary part of the dielectric function is zero, a regime where in a non-retarded treatment no loss or coupling can occur. Maps of the resultant energy losses as a sub-5nm electron probe scans across finite waveguide structures reveal spatial distributions of optical modes in a spectral domain ranging from near-infrared to far ultraviolet.

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Judy J. Cha, Zongfu Yu, Eric Smith, Martin Couillard, Shanhui Fan, David A. Muller. 2010-02-18. Mapping local optical densities of states in silicon photonic structures with nanoscale electron spectroscopy. https://doi.org/10.1103/physrevb.81.113102

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