Time-resolved terahertz spectroscopy is used to probe ultrafast carrier dynamics and terahertz conductivity in photoexcited thin films of silicon nanocrystals, polynanocrystalline silicon, and epitaxial silicon-on-sapphire. We show that a Drude-Smith model provides an excellent fit to the observed transient terahertz conductivity in all of our samples, revealing a transition from a Drude-like response with low carrier backscatter in bulk silicon-on-sapphire to a non-Drude-like, localized behavior with high carrier backscatter in the silicon nanocrystal films. Evidence for long-range conduction between nanocrystals is observed, and we show that the photoconductive lifetime of the silicon nanocrystals is dominated by trapping at Si/SiO2 interface states.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据