Showing papers by "Mark W. Knight published in 2011"
TL;DR: An active optical antenna-diode combines the functions of light-harvesting and excited-electron injection, and is a highly compact, wavelength-resonant, and polarization-specific light detector, with a spectral response extending to energies well below the semiconductor band edge.
Abstract: Nanoantennas are key optical components for light harvesting; photodiodes convert light into a current of electrons for photodetection. We show that these two distinct, independent functions can be combined into the same structure. Photons coupled into a metallic nanoantenna excite resonant plasmons, which decay into energetic, "hot" electrons injected over a potential barrier at the nanoantenna-semiconductor interface, resulting in a photocurrent. This dual-function structure is a highly compact, wavelength-resonant, and polarization-specific light detector, with a spectral response extending to energies well below the semiconductor band edge.
1,828 citations
TL;DR: Investigation of the light-triggered release of DNA from two types of nanoparticle substrates suggests that a nonthermal mechanism may play a role in plasmon resonant, light- triggered DNA release.
Abstract: Plasmon-resonant nanoparticle complexes show highly promising potential for light-triggered, remote-controlled delivery of oligonucleotides on demand, for research and therapeutic purposes. Here we investigate the light-triggered release of DNA from two types of nanoparticle substrates: Au nanoshells and Au nanorods. Both light-triggered and thermally induced release are distinctly observable from nanoshell-based complexes, with light-triggered release occurring at an ambient solution temperature well below the DNA melting temperature. Surprisingly, no analogous measurable release was observable from nanorod-based complexes below the DNA melting temperature. These results suggest that a nonthermal mechanism may play a role in plasmon resonant, light-triggered DNA release.
343 citations
Patent•
11 Nov 2011
TL;DR: In this paper, the authors describe a unit that includes a semiconductor and a plasmonic material disposed on the semiconductor, where a potential barrier is formed between the material and the material.
Abstract: In general, the invention relates to a unit that includes a semiconductor and a plasmonic material disposed on the semiconductor, where a potential barrier is formed between the plasmonic material and the semiconductor. The unit further includes an insulator disposed on the semiconductor and adjacent to the plasmonic material and a transparent conductor disposed on the plasmonic material, where, upon illumination, the plasmonic material is excited resulting the excitation of an electron with sufficient energy to overcome the potential barrier.
7 citations