Tang, L., Kocabas, S. E., Latif, S., Okyay, A. K., Ly-Gagnon, D. - S., Saraswat, K. C., et al. (2008). Nanometre-scale germanium photodetector enhanced by a near-infrared dipole antenna. Nature Photonics, 2, 226–229.
Abstract: A critical challenge for the convergence of optics and electronics is that the micrometre scale of optics is significantly larger than the nanometre scale of modern electronic devices. In the conversion from photons to electrons by photodetectors, this size incompatibility often leads to substantial penalties in power dissipation, area, latency and noise. A photodetector can be made smaller by using a subwavelength active region; however, this can result in very low responsivity because of the diffraction limit of the light. Here we exploit the idea of a half-wave Hertz dipole antenna (length approx 380 nm) from radio waves, but at near-infrared wavelengths (length approx 1.3 microm), to concentrate radiation into a nanometre-scale germanium photodetector. This gives a polarization contrast of a factor of 20 in the resulting photocurrent in the subwavelength germanium element, which has an active volume of 0.00072 microm3, a size that is two orders of magnitude smaller than previously demonstrated detectors at such wavelengths.
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Bharadwaj, P., Deutsch, B., & Novotny, L. (2009). Optical Antennas. Adv. Opt. Photon, 1, 438–483.
Abstract: Optical antennas are an emerging concept in physical optics. Similar to radiowave
and microwave antennas, their purpose is to convert the energy of free propagating radiation to localized energy, and vice versa. Optical antennas exploit the unique properties of metal nanostructures, which behave as strongly coupled plasmas at ptical frequencies. The tutorial provides an account of the historical origins and the basic concepts and parameters associated with optical antennas. It also reviews recent work in the field and discusses areas of application, such as light-emitting devices, photovoltaics, and spectroscopy.
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Hu, X., Dauler, E. A., Kerman, A. J., Yang, J. K. W., White, J. E., Herder, C. H., et al. (2009). Using surface plasmons to enhance the speed and efficiency of superconducting nanowire single-photon detectors. In Proceedings of the Conference on Lasers and Electro-Optics, 2009 and 2009 Conference on Quantum electronics and Laser Science Conference (pp. 1–2).
Abstract: We report our design and fabrication of superconducting nanowire single-photon detectors integrated with gold plasmonic nanostructures, which can enhance the absorption of TM-polarized light, and can enlarge the effective area without sacrificing detector speed.
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Saynak, U. Ä. Ÿ. (2008). Novel rectangular spiral antennas.
Abstract: Round spiral antennas are generally designed by using Archimedean spiral geometries which have linear growth rates. To obtain smaller antennas with nearly the same performance, square spiral Archimedean geometries are also widely used instead. In this study, novel square antennas are proposed, designed and examined. At first two similar but different approaches are employed to design new antennas by considering the design procedure used to obtain log-periodic antennas. Then, the performance of these antennas is improved by considering another property of log-periodic antennas. Simulations are performed by using two different numerical methods which are Finite Difference Time Domain Method (FDTD) and Method of Moments (MoM). The results obtained from the simulations are compared with those of the Archimedean spiral antennas in terms of the frequency dependency of fundamental antenna parameters such as antenna gain and radiation pattern. The simulation results are compared with the ones obtained from the experimental study.
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Kramer, B., Chen, C. - C., & Volakis, J. D. (2004). The development of a mini-UWB antenna. AMTA, , 6.
Abstract: There is a great interest in the automotive and military sectors for small and broadband antennas that meet modern communication needs. These needs require ultra-wide bandwidth (>10:1) UWB antennas, such as the spiral antenna. However, the physical size at the low-frequency end typically becomes too large for practical applications. To reduce the size of the antenna, miniaturization techniques must be employed such as the use of high-contrast dielectric materials. Size reduction using high-contrast materials has been demonstrated for narrowband antennas, such as patch antennas, but not for broadband antennas to our knowledge. Therefore, the concept of miniaturizing a broadband spiral antenna using dielectric materials will be investigated experimentally and numerically.Issues that arise from dielectric loading such as impedance reduction will also be addressed. It will be shown using the results from these studies that there are practical limitations to the amount of miniaturization which can be achieved.
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