Hot-electron generation in plasmonic nanostructures with hot spots: Quantum mechanisms

Generation of energetic (hot) electrons is an intrinsic property of any plasmonic nanostructure under illumination. Simultaneously, a striking advantage of metal nanocrystals over semiconductors lies in their very large absorption cross sections. Therefore, metal nanostructures with strong and tailored plasmonic resonances are very attractive for photocatalytic applications in which excited electrons play an important role. However, the central question in this problem is to quantify the number of hot electrons in a nanocrystal. Here we develop a theory describing the energy distributions of hot electrons in nanocrystals with various geometries [1-4]. In particular, we show that nanostructures with strong plasmonic hot spots generate unusually large numbers of hot electrons, which can be observed using ultra-fast spectroscopy, [2,4] and photochemistry.
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