Now showing items 1-16 of 16

    • Comparative study of thin film n-i-p a-Si: H solar cells to investigate the effect of absorber layer thickness on the plasmonic enhancement using gold nanoparticles 

      Islam, K.; Chowdhury F.I.; Okyay, Ali Kemal; Nayfeh, A. (Elsevier Ltd, 2015)
      In this paper, the effect of gold nanoparticles on n-i-p a-Si:H solar cells with different intrinsic layer (i-layer) thicknesses has been studied. 100nm and 500nm i-layer based n-i-p a-Si:H solar cells were fabricated and ...
    • Compound Hertzian chain model for copper-carbon nanocomposites' absorption spectrum 

      Kokabi, A.; Hosseini, M.; Saeedi, S.; Moftakharzadeh, A.; Vesaghi, M.A.; Fardmanesh, M. (2011)
      The infrared range optical absorption mechanism of carbon-copper composite thin layer coated on the diamond-like carbon buffer layer has been investigated. By consideration of weak interactions between copper nanoparticles ...
    • Critical coupling in plasmonic resonator arrays 

      Balci, S.; Kocabas, C.; Aydınlı, Atilla (Optical Society of America, 2011)
      We report critical coupling of electromagnetic waves to plasmonic cavity arrays fabricated on Moiré surfaces. Dark field plasmon microscopy imaging and polarization dependent spectroscopic reflection measurements reveal ...
    • Direct imaging of localized surface plasmon polaritons 

      Balcı, Sinan; Karademir, Ertuğrul; Kocabaş, Coşkun; Aydınlı, Atilla (Optical Society of America, 2011-08)
      In this Letter, we report on dark field imaging of localized surface plasmon polaritons (SPPs) in plasmonic waveguiding bands formed by plasmonic coupled cavities. We image the light scattered from SPPs in the plasmonic ...
    • LSPR enhanced MSM UV photodetectors 

      Butun, S.; Cinel, N. A.; Özbay, Ekmel (IOP Publishing, 2012-10-18)
      We fabricated localized surface plasmon resonance enhanced UV photodetectors on MOCVD grown semi-insulating GaN. Plasmonic resonance in the UV region was attained using 36nm diameter Al nanoparticles. Extinction spectra ...
    • Plasmonic absorbers for multispectral and broadband absorption 

      Ayaş, Sencer; Güner, Hasan; Türker, Burak; Ekiz, Öner; Dana, Aykutlu (SPIE, 2012)
      We present polarization dependent multispectral and broadband plasmonic absorbers in the visible spectrum. The spectral characteristics of these structures are tunable over a broad spectrum. Experimental results are verified ...
    • A plasmonic enhanced photodetector based on silicon nanocrystals obtained through laser ablation 

      Alkis, S.; Oruç, F. B.; Ortaç, B.; Koşger, A. C.; Okyay, Ali Kemal (Institute of Physics Publishing, 2012-10-18)
      We present a proof-of-concept photodetector which is sensitive in the visible spectrum. Silicon nanocrystals (Si-NCs) obtained by laser ablation are used as the active absorption region. Si-NC films are formed from a ...
    • Plasmonic gratings for enhanced near infrared sensitivity of Silicon based Schottky photodetectors 

      Polat, Kazım Gürkan; Aygun, Levent Erdal; Okyay, Ali Kemal (IEEE, 2011)
      Schottky photodetectors have been intensively investigated due to their high speeds, low device capacitances, and sensitivity in telecommunication standard bands, in the 0.8μm to 1.5μm wavelength range. Due to extreme cost ...
    • Plasmonic nanoslit array enhanced metal-semiconductor-metal optical detectors 

      Eryilmaz, S. B.; Tidin, O.; Okyay, Ali Kemal (Institute of Electrical and Electronics Engineers, 2012-01-09)
      Metallic nanoslit arrays integrated on germanium metal-semiconductor-metal photodetectors show many folds of absorption enhancement for transverse-magnetic polarization in the telecommunication C-band. Such high enhancement ...
    • Raman enhancement on a broadband meta-surface 

      Ayas S.; Güner, H.; Türker, B.; Ekiz, O. O.; Dirisaglik, F.; Okyay, Ali Kemal; Dâna, A. (American Chemical Society, 2012-07-30)
      Plasmonic metamaterials allow confinement of light to deep subwavelength dimensions, while allowing for the tailoring of dispersion and electromagnetic mode density to enhance specific photonic properties. Optical resonances ...
    • Retrieval of effective parameters for bianisotropic metamaterials with omega shaped metallic inclusions 

      Li, Z.; Aydin, K.; Özbay, Ekmel (Elsevier, 2011-11-18)
      Bianisotropic metamaterials including Ω-shaped metallic elements are investigated experimentally and theoretically. A passband is observed for a composite metamaterial (CMM) based on an Ω-medium below the plasmonic frequency ...
    • Slowing surface plasmon polaritons on plasmonic coupled cavities by tuning grating grooves 

      Balcı, Sinan; Kocabaş, Aşkın; Kocabaş, Coşkun; Aydınlı, Atilla (American Institute of Physics, 2010-09)
      We investigate slow surface plasmon polaritons (SPPs) in plasmonic waveguiding bands formed by coupled plasmonic cavities on Moiŕ surfaces. We demonstrate controlling the group velocity and dispersion of the SPPs by varying ...
    • Strong light-matter interaction in lithography-free planar metamaterial perfect absorbers 

      Ghobadi, A.; Hajian, H.; Butun, B.; Özbay, Ekmel (American Chemical Society, 2018)
      The efficient harvesting of electromagnetic (EM) waves by subwavelength nanostructures can result in perfect light absorption in the narrow or broad frequency range. These metamaterial-based perfect light absorbers are of ...
    • Tunable plasmonic silver nanodomes for surface-enhanced raman scattering 

      Kahraman, M.; Ozbay, A.; Yuksel, H.; Solmaz, R.; Demir, B.; Caglayan, H. (Springer, 2018)
      Surface-enhanced Raman scattering (SERS) is an emerging analytical method used in biological and non-biological structure characterization. Since the nanostructure plasmonic properties is a significant factor for SERS ...
    • Ultra-low-cost broad-band near-infrared silicon photodetectors based on hot electrons 

      Nazirzadeh, Mohammad Amin (Bilkent University, 2015)
      Silicon is at the heart of all of the end-user digital devices such as smart phones, laptops, and wearable technologies. It is the holy grail for the largescale production of semiconductor devices since start of the ...
    • Volumetric plasmonic resonator architecture for thin-film solar cells 

      Sefunc, M.A.; Okyay, Ali Kemal; Demir, Hilmi Volkan (AIP Publishing, 2011-03-04)
      We propose and demonstrate a design concept of volumetric plasmonic resonators that relies on the idea of incorporating coupled layers of plasmonic structures embedded into a solar cell in enhanced optical absorption for ...