C-shaped nanoaperture-enhanced germanium photodetector

Center for Integrated Systems, Stanford University, Palo Alto, California, United States
Optics Letters (Impact Factor: 3.29). 06/2006; 31(10):1519-21. DOI: 10.1364/OL.31.001519
Source: PubMed


We present a C-shaped nanoaperture-enhanced Ge photodetector that shows 2-5 times the photocurrent enhancement over that from a square aperture of the same area at 1310 nm wavelength. We demonstrate the polarization dependence of the C-aperture photodetector over a wide wavelength range. Our experimental observation agrees well with finite-difference time-domain simulation results.

Download full-text


Available from: Ali K. Okyay
  • Source
    • "As a result, the self-conductance and mutual conductances for both the maximum and minimum transmitted power in the case of the ridged circular apertures are found to be very similar to the self-resistance and mutual resistances for both the maximum and minimum gains of dipole antenna arrays, allowing the establishment of a duality between them. The usage of a resonant ridged aperture has already been proposed in many applications, including nanoscale lithography [22], single-molecule fluorescence measurement [23], and optical data storage [24] [25] [26] [27], and so on [28] [29] [30], and this study may be a stepping stone from the single resonant aperture to two-dimensional array of the aperture, for example, a frequency selective surface (FSS) [31], a significant electromagnetic structure with many potential applications. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The resonant microwave transmission characteristics of several coupled subwavelength ridged circular aperture arrangements in a thin metallic film are investigated using the three-dimensional finite-difference time-domain (3D FDTD) method. Simple equivalent circuits represented by the self and mutual conductances that have been quantitatively extracted for each resonance condition, including the mutual coupling effects, are also devised with the help of virtual magnetic current elements. Furthermore, a duality is identified between the ridged circular apertures and conventional half-wavelength dipole arrays based on comparing the respective resonance conditions.
    Full-text · Article · Dec 2012 · International Journal of Antennas and Propagation
  • Source
    • "Nanometallic structures can be used to concentrate optical energy to a very small scale, exploiting surface plasmonic waves. Experimentally, a factor of 5× enhancement in optical absorption has been demonstrated in [17], and in principle, it is possible to further increase this factor. The performance of the OE switch can be improved by concentrating light on such small dimensions as the gate of the optical MOSFET pair. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We propose a novel semiconductor optoelectronic (OE) switch that is a fusion of a Ge optical detector and a Si metal-oxide-semiconductor (MOS) field-effect transistor (FET). The device operation principle is investigated, and the performance is explored by simulations. The proof of principle is demonstrated by experiments. The use of Ge enables operation in standard telecommunication wavelengths, in addition to providing the surrounding Si circuitry with noise immunity from signaling. The transconductance of the FET provides amplification, and an experimental current gain of up to 1000 is demonstrated. A complementary function is shown by tailoring the doping profiles. The circuit performance of a complementary pair using the International Technology Roadmap for Semiconductors values for the 150-nm node is evaluated by simulation, yielding ~100-ps cycle times. The switch can be fabricated in the nanoscale regime along with a high-performance Si complementary MOS. A very low capacitance can be achieved due to the isolation of the detection region from the current drive. OE conversion that is performed with such a compact device offers the potential of inserting light at the latch level in a microprocessor.
    Full-text · Article · Jan 2008 · IEEE Transactions on Electron Devices
  • Source
    • "We have recently been able to demonstrate enhancement of photodetection with nanopatterned metallic structures. A small Cshaped aperture in a metal film on a germanium substrate [15] gives a larger photocurrent per unit semiconductor volume than can be achieved without such metallic structures. This observation is very promising for the use of nanometallic structures to enhance optoelectronic devices. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Quantum well structures in germanium and nanophotonic structures in dielectrics and metals promise future optics, optoelectronics and electronics, all possibly combined in one silicon compatible platform. Challenges, approaches and recent progress are summarized.
    Full-text · Conference Paper · Jun 2007
Show more