ABSTRACT
Plasmon-resonant gold nanorods (GNR) have large absorption cross sections at near-infrared (NIR) frequencies and can support a variety of linear and nonlinear optical phenomena, several of which can be used to enable or enhance the contrast of optical imaging modalities. GNRs can also mediate the efficient conversion of NIR light energy into heat, with subsequent application toward local photothermal effects. GNRs are especially attractive due to the tunability of their plasmon resonances, and also their straightforward and highly reproducible synthesis. Plasmon-resonant scattering from GNRs has been investigated by confocal and darkfield microscopy, and also modeled using numerical approaches. GNRs exhibit several nonlinear optical properties, generated upon plasmon-resonant excitation with ultrashort laser pulses. Surface engineering plays a critical role in the development of GNRs for biomedical applications. GNRs are much better suited to support Optical coherence tomography modalities based on differential absorption or backscattering albedo, which have the advantage of producing contrast in tissues with intrinsically high scattering cross sections.
