Published on Thursday April 6, 2006
New findings may soon enable silicon to play an expanded role in electronics and photonics. As reported by Cao, et al. in the upcoming April 21st issue of Physical Review Letters, a Drexel University research team led by Materials Science and Engineering Professor Jonathan E. Spanier has identified a remarkable feature of silicon nanowires (SiNWs) and silicon nanocones (SiNCs): individually-probed SiNWs and SiNCs scatter visible light up to three orders of magnitude more efficiently than Si in its bulk form.
SiNWs are important building blocks of nanotechnology: owing to their size-dependent properties and the strong influence of surface chemistry on these properties, they are highly attractive components in a range of high-performance electronic devices, including high-sensitivity biological and chemical probes for detection of diseases and for environmental monitoring.
The resonantly-enhanced electromagnetic fields within and at the surfaces of the non-metallic SiNWs and SiNCs suggest new opportunities for integrating electronics and photonics in nanostructured silicon, and for applications involving detection, identification, characterization and manipulation of individual molecules on chemically-functionalized nanowire surfaces. Cao, et al. explain the results in terms of resonant interaction of the light with the SiNW and SiNC cross-section; this effect is expected to be found in a range of other nanowire and nanocone materials.