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arXiv · 1311.6970

Studies of hot photoluminescence in plasmonically-coupled silicon via variable energy excitation and temperature dependent spectroscopy

Carlos O. Aspetti·Chang-Hee Cho·Rahul Agarwal·Ritesh Agarwal
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Abstract

By coupling silicon nanowires (~150 nm diameter, 20 micron length) with an Ω-shaped plasmonic nanocavity we are able to generate broadband visible luminescence, which is induced by high-order hybrid nanocavity-surface plasmon modes. The nature of this super-bandgap emission is explored via photoluminescence spectroscopy studies performed with variable laser excitation energies (1.959 eV to 2.708 eV) and finite difference time domain simulations. Furthermore, temperature-dependent photoluminescence spectroscopy shows that the observed emission corresponds to radiative recombination of un-thermalized (hot) carriers as opposed to a Resonant Raman process.

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Carlos O. Aspetti, Chang-Hee Cho, Rahul Agarwal, Ritesh Agarwal. 2013-11-27. Studies of hot photoluminescence in plasmonically-coupled silicon via variable energy excitation and temperature dependent spectroscopy. https://doi.org/10.1021/nl502606q

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