Plasmonic Doped Semiconductor Nanocrystals: Properties, Fabrication, Applications and Perspectives

TL;DR

Degenerately doped semiconductor nanocrystals exhibit tunable localized surface plasmon resonances in the near infrared, offering versatile optical properties and promising applications distinct from noble metals.

Contribution

This paper reviews the properties, fabrication, and applications of plasmonic doped semiconductor nanocrystals, highlighting their unique LSPR tuning mechanisms and potential uses.

Findings

LSPR tuning in copper chalcogenide NCs involves structural changes.

Impurity doping in metal oxide NCs modifies LSPR through different mechanisms.

Plasmonic semiconductor NCs have unique optical properties and diverse applications.

Abstract

Degenerately doped semiconductor nanocrystals (NCs) are of recent interest to the NC community due to their tunable localized surface plasmon resonances (LSPRs) in the near infrared (NIR). The high level of doping in such materials with carrier densities in the range of 1021 cm^-3 leads to degeneracy of the doping levels and intense plasmonic absorption in the NIR. The lower carrier density in degenerately doped semiconductor NCs compared to noble metals enables LSPR tuning over a wide spectral range, since even a minor change of the carrier density strongly affects the spectral position of the LSPR. We focus on copper chalcogenide NCs and impurity doped metal oxide NCs as the most investigated alternatives to noble metals. We shed light on the structural changes upon LSPR tuning in vacancy doped copper chalcogenide NCs and deliver a picture for the fundamentally different mechanism of LSPR modification of impurity doped metal oxide NCs. We review on the peculiar optical properties of plasmonic degenerately doped NCs by highlighting the variety of different optical measurements and optical modeling approaches. These findings are merged in an exhaustive section on new and exciting applications based on the special characteristics that plasmonic semiconductor NCs bring along.