Localized Surface Plasmon Resonances of Anisotropic Semiconductor Nanocrystals

2011-11-30T00:00:00Z (GMT) by Su-Wen Hsu Kathy On Andrea R. Tao
We demonstrate that anisotropic semiconductor nanocrystals display localized surface plasmon resonances that are dependent on the nanocrystal shape and cover a broad spectral region in the near-IR wavelengths. In-plane and out-of-plane dipolar resonances were observed for colloidal dispersions of Cu2–xS nanodisks, and the wavelengths of these resonances are in good agreement with calculations carried out in the electrostatic limit. The wavelength, line shape, and relative intensities of these plasmon bands can be tuned during the synthetic process by controlling the geometric aspect ratio of the disk or using a postsynthetic thermal-processing step to increase the free carrier densities.