Localized Surface Plasmon Resonances of Anisotropic Semiconductor Nanocrystals

Abstract

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 Cu(2-x)S 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.

Colloidal Cu2−x(SySe1−y) alloy nanocrystals with controllable crystal phase: synthesis, plasmonic properties, cation exchange and electrochemical lithiation

“…''x'') by means of reversible oxidation/reduction processes. 19,22 In a recent article on Cu 2Àx Se nanodisks, both in-plane and out-of-plane plasmon resonances were detected, in accordance with calculations based on the electrostatic approximation, 23 which makes these plasmonic semiconductor NCs similar to noble metal NCs.…”

New materials for tunable plasmonic colloidal nanocrystals

“…According to them, the partial localization of the carriers in copper chalcogenide nanorods could also be related to structural disorder, 29 in particular to the existence of a mobility edge, which would cause the localization of the holes with energy below a certain threshold. 29 On a similar note, efforts have been undertaken to identify the possible presence of multiple LSPRs in nanodisks of copper 70 and observed two optical absorption bands (one at 1800 and the other at 3100 nm), which they attributed to an out-of-plane longitudinal and in-plane plasmon mode, respectively. Differently from what could be expected based on the theory, 1 both LSPRs were blue shifted as the aspect ratio of the nanodisks was increased.…”

Semiconducting and Plasmonic Copper Phosphide Platelets

“…Similar absorption in this region has previously been reported for Cu 2 S and Cu 2 Se, and is mostly due to localized surface plasmon resonance (LSPR). [5][6][7][8]18] However, this has been observed for the first time in Cu 3 P. This plasmonic absorbance is further supported by the tuning of the absorption energy with variation of the dispersion mediums of different refractive index. A typical example of solutions in CCl 4 , CS 2 , and C 2 Cl 4 suggests that the absorption (Figure 4 c).…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Furthermore, materials with rectification properties remain one of the most demanding materials in recent times. [1][2][3][4][14][15][16][17] Very recently, semiconducting nanomaterials with tunable plasmonic absorption properties have also been reported; [5][6][7][8][18][19][20][21][22] these may further expand the already widespread applications of these nanomaterials in diverse research fields, including both in biology and device-based technologies. Hence, materials with several of these new properties are in demand for their implementation in different developing modern technologies.…”