Redesigning Photodetector Electrodes as an Optical Antenna

Nano Letters (Impact Factor: 13.59). 01/2013; 13(2). DOI: 10.1021/nl303535s
Source: PubMed


At the nanoscale, semiconductor and metallic structures naturally exhibit strong, tunable optical resonances that can be utilized to enhance light-matter interaction and to dramatically increase the performance of chipscale photonic elements. Here, we demonstrate that the metallic leads used to extract current from a Ge nanowire (NW) photodetector can be redesigned to serve as optical antennas capable of concentrating light in the NW. The NW itself can also be made optically resonant and an overall performance optimization involves a careful tuning of both resonances. We show that such a procedure can result in broadband absorption enhancements of up to a factor 1.7 at a target wavelength of 660 nm and an ability to control the detector's polarization-dependent response. The results of this study demonstrate the critical importance of performing a joint optimization of the electrical and optical properties of the metallic and semiconductor building blocks in optoelectronic devices with nanoscale components.

22 Reads
  • Source
    • "Excellent electronic transport properties of silicon nanowires can be exploited for biomolecule detection in the dc and frequency dependent detection systems [1]. Germanium and silicon-based nanowire devices can absorb and transduce light to photocurrent [2] [3] [4]. The addition of optical antennas in the nanowire device enhances photodetection by concentrating radiation into a semiconductor nanowire. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Properties of surface plasmon polaritons can be exploited for the miniaturisation of photonic circuits below the optical wavelength scale. Smaller and more sensitive photodetectors can be made by using sub-wavelength semiconductor elements such as germanium or silicon nanowires in combination with nanometer-scale antennas. The proposed nanowire photodetector enables on-chip optical sensing applications with increased sensitivity and reduced size.
    Applied Physics A 11/2013; DOI:10.1007/s00339-013-8070-z · 1.70 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A plasmonic enhanced Schottky diode is proposed and investigated with metallic periodic slits. A narrow-band response (~40nm) could be tuned in a wide spectrum (800~1800nm) by varying the period of the slits.
    Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2013 Conference on; 06/2013
  • [Show abstract] [Hide abstract]
    ABSTRACT: I will discuss nanoscale optoelectronic devices composed of optically resonant semiconductor and metallic building blocks, including sources, modulators, and photodetectors 150-word Biography: Mark Brongersma is an Associate Professor and Keck Faculty Scholar in the Department of Materials Science and Engineering at Stanford University. He leads a research team of ten students and three postdocs. Their research is directed towards the development and physical analysis of new materials and structures that find use in nanoscale electronic and photonic devices. He received a National Science Foundation Career Award, the Walter J. Gores Award for Excellence in Teaching, the International Raymond and Beverly Sackler Prize in the Physical Sciences (Physics) for his work on plasmonics, and is a Fellow of the Optical Society of America, the SPIE, and the American Physical Society. Dr. Brongersma received his PhD in Materials Science from the FOM Institute in Amsterdam, The Netherlands, in 1998. From 1998-2001 he was a postdoctoral research fellow at the California Institute of Technology.
    CLEO: Science and Innovations; 06/2013
Show more