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تسجيل مستخدم جديدStudies of hot photoluminescence in plasmonically-coupled silicon via variable energy excitation and temperature dependent spectroscopy
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By coupling silicon nanowires (~150 nm diameter, 20 micron length) with an {Omega}-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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