Hayden Oliver, Agarwal Ritesh, Lieber Charles M
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nat Mater. 2006 May;5(5):352-6. doi: 10.1038/nmat1635. Epub 2006 Apr 16.
Integrating nanophotonics with electronics could enhance and/or enable opportunities in areas ranging from communications and computing to novel diagnostics. Light sources and detectors are important elements for integration, and key progress has been made using semiconducting nanowires and carbon nanotubes to yield electrically driven sources and photoconductor detectors. Detection with photoconductors has relatively poor sensitivity at the nanometre scale, and thus large amplification is required to detect low light levels and ultimately single photons with reasonable response time. Here, we report avalanche multiplication of the photocurrent in nanoscale p-n diodes consisting of crossed silicon-cadmium sulphide nanowires. Electrical transport and optical measurements demonstrate that the nanowire avalanche photodiodes (nanoAPDs) have ultrahigh sensitivity with detection limits of less than 100 photons, and subwavelength spatial resolution of at least 250 nm. Crossed nanowire arrays also show that nanoAPDs are reproducible and can be addressed independently without cross-talk. NanoAPDs and arrays could open new opportunities for ultradense integrated systems, sensing and imaging applications.
将纳米光子学与电子学相结合，可以增强和/或创造从通信、计算到新型诊断等领域的机会。光源和探测器是集成的重要元件，利用半导体纳米线和碳纳米管来制造电驱动光源和光电导探测器已取得关键进展。使用光电导体进行检测在纳米尺度下灵敏度相对较差，因此需要大幅放大才能在合理的响应时间内检测低光水平并最终检测单光子。在此，我们报告了由交叉的硅 - 硫化镉纳米线组成的纳米级 p - n 二极管中光电流的雪崩倍增现象。电学输运和光学测量表明，纳米线雪崩光电二极管（nanoAPD）具有超高灵敏度，检测极限小于 100 个光子，亚波长空间分辨率至少为 250 nm。交叉纳米线阵列还表明，nanoAPD 具有可重复性，并且可以独立寻址而无串扰。nanoAPD 及其阵列可为超密集集成系统、传感和成像应用带来新机遇。
