Now showing items 1-20 of 20

    • 1.3 μm GaAs based resonant cavity enhanced Schottky barrier internal photoemission photodetector 

      Necmi, B.; Kimukin, I.; Özbay, Ekmel; Tuttle, G. (IEEE, Piscataway, NJ, United States, 2000)
      GaAs based photodetectors operating at 1.3 μm that depend on internal photoemission as the absorption mechanism were fabricated. Quantum efficiency (QE) was increased using resonant cavity enhancement (RCE) effect.
    • Defect structures in a layer-by-layer photonic band-gap crystal 

      Özbay, Ekmel; Tuttle, G.; Sigalas, M.; Soukoulis, C. M.; Ho, K. M. (American Physical Society, 1995)
      We have experimentally and theoretically investigated defect structures that are incorporated into a three-dimensional layer-by-layer photonic band-gap crystal. The defects are formed by either adding or removing dielectric ...
    • Defect structures in metallic photonic crystals 

      Özbay, Ekmel; Temelkuran, B.; Sigalas, M.; Tuttle, G.; Soukoulis, C. M.; Ho, K. M. (A I P Publishing LLC, 1996-12-16)
      We have investigated metallic photonic crystals built around a layer‐by‐layer geometry. Two different crystal structures (face‐centered‐tetragonal and tetragonal) were built and their properties were compared. We obtained ...
    • Fabrication of high-speed resonant cavity enhanced schottky photodiodes 

      Özbay, Ekmel; Islam, M. S.; Onat, B.; Gökkavas, M.; Aytür, O.; Tuttle, G.; Towe, E.; Henderson, R. H.; Ünlü, M. S. (Institute of Electrical and Electronics Engineers, 1997-05)
      We report the fabrication and testing of a GaAs-based high-speed resonant cavity enhanced (RCE) Schottky photodiode. The top-illuminated RCE detector is constructed by integrating a Schottky contact, a thin absorption ...
    • High-speed 1.3 μm GaAs internal photoemission resonant cavity enhanced photodetector 

      Kimukin, İbrahim; Özbay, Ekmel; Bıyıklı, Necmi; Kartaloğlu, Tolga; Aytür, Orhan; Tuttle, G. (IEEE, 2000)
      Resonant cavity enhanced (RCE) photodetectors offer the possibility of overcoming the low quantum efficiency limitation of conventional photodetectors. The RCE detectors are based on the enhancement of the optical field ...
    • High-speed GaAs-based resonant-cavity-enhanced 1.3 μm photodetector 

      Kimukin, I.; Özbay, Ekmel; Bıyıklı, Necmi; Kartaloğlu, T.; Aytür, O.; Unlu, S.; Tuttle, G. (American Institute of Physics., 2000)
      We report GaAs-based high-speed, resonant-cavity-enhanced, Schottky barrier internal photoemission photodiodes operating at 1.3 μm. The devices were fabricated by using a microwave-compatible fabrication process. Resonance ...
    • High-speed high-efficiency resonant cavity enhanced photodiodes 

      Özbay, Ekmel; Kimukin, I.; Bıyıklı, N.; Aytür, O.; Gökkavas, M.; Ulu, G.; Ünlü, M. S.; Mirin, R. P.; Bertness, K. A.; Christensen, D. H.; Towe, E.; Tuttle, G. (Society of Photo-Optical Instrumentation Engineers, Bellingham, WA, United States, 1999)
      In this paper, we review our research efforts on RCE high-speed high-efficiency p-i-n and Schottky photodiodes. Using a microwave compatible planar fabrication process, we have designed and fabricated GaAs based RCE ...
    • High-speed resonant-cavity-enhanced Schottky photodiodes 

      Ata, Erhan P.; Bıyıklı, Necmi; Demirel, Ekrem; Özbay, Ekmel; Gökkavas, M.; Onat, B.; Ünlü, M. S.; Tuttle, G. (IEEE, 1998)
      The top-illuminated Schottky photodiodes were fabricated by a microwave-compatible monolithic microfabrication process. Fabrication started with formation of ohmic contacts to n+ layers. Mesa isolation was followed by a ...
    • Highly directional resonant antennas built around photonic crystals 

      Özbay, Ekmel; Temelkuran, Burak; Bayındır, Mehmet; Biswas, R.; Sigalas, M. M.; Tuttle, G.; Ho, K. M. (IEEE, 1999)
      We report a photonic crystal-based resonant antenna with a very high directivity and gain. The layer-by-layer dielectric photonic crystal we used in our experiments was designed to have a three dimensional band gap with a ...
    • Highly doped silicon micromachined photonic crystals 

      Temelkuran, B.; Bayındır, Mehmet; Özbay, Ekmel; Kavanaugh, J. P.; Sigalas, M. M.; Tuttle, G. (IEEE, Piscataway, NJ, United States, 2000)
      Summary form only given. Photonic crystals are periodic structures with the property of reflecting the electromagnetic (EM) waves in all directions within a certain frequency range. These structures can be used to control ...
    • Laser-micromachined millimeter-wave photonic band-gap cavity structures 

      Özbay, Ekmel; Tuttle, G.; McCalmont, J. S.; Sigalas, M.; Biswas, R.; Soukoulis, C. M.; Ho, K. M. (American Institute of Physics, 1995)
      We have used laser-micromachined alumina substrates to build a three-dimensional photonic band-gap crystal. The rod-based structure has a three-dimensional full photonic band gap between 90 and 100 GHz. The high resistivity ...
    • Microwave applications of photonic band gap structures 

      Temelkuran, Burak; Bayındır, Mehmet; Özbay, Ekmel; Biswas, R.; Sigalas, M. M.; Tuttle, G.; Ho, K.-M. (IEEE, 2000-10)
      We have investigated two major applications of photonic band gap materials. We demonstrated the guiding and bending of electromagnetic waves through planar waveguides built around layer-by-layer photonic crystals. We then ...
    • Negative refraction and superlens behavior in a two-dimensional photonic crystal 

      Moussa, R.; Foteinopoulou, S.; Zhang, L.; Tuttle, G.; Guven, K.; Özbay, Ekmel; Soukoulis, C. M. (American Physical Society, 2005)
      We experimentally and theoretically studied a left-handed structure based on a photonic crystal (PC) with a negative refractive index. The structure consists of triangular array of rectangular dielectric bars with dielectric ...
    • Optimized dipole antennas on photonic band gap crystals 

      Cheng, S. D.; Biswas, R.; Özbay, Ekmel; McCalmont, S.; Tuttle, G.; Ho, K.-M. (American Institute of Physics, 1995)
      Photonic band gap crystals have been used as a perfectly reflecting substrate for planar dipole antennas in the 12-15 GHz regime. The position, orientation, and driving frequency of the dipole antenna on the photonic band ...
    • Photonic crystal-based resonant antenna with a very high directivity 

      Temelkuran, B.; Bayındır, Mehmet; Özbay, Ekmel; Biswas, R.; Sigalas, M. M.; Tuttle, G.; Ho, K. M. (American Institute of Physics, 2000-09-24)
      We investigate the radiation properties of an antenna that was formed by a hybrid combination of a monopole radiation source and a cavity built around a dielectric layer-by-layer three-dimensional photonic crystal. We ...
    • Photonic-crystal-based resonant-cavity-enhanced detectors 

      Temelkuran, Burak; Özbay, Ekmel; Kavanaugh, J. P.; Tuttle, G.; Ho, K. M. (IEEE, 1998)
      A layer-by-layer three-dimensional photonic crystal, with a full photonic bandgap (PBG) in all directions is proposed. The electrical fields in the cavities of this crystal are usually enhanced, and by placing active devices ...
    • Quasimetallic silicon micromachined photonic crystals 

      Temelkuran, B.; Bayındır, Mehmet; Özbay, Ekmel; Kavanaugh, J. P.; Sigalas, M. M.; Tuttle, G. (American Institute of Physics, 2001)
      We report on fabrication of a layer-by-layer photonic crystal using highly doped silicon wafers processed by semiconductor micromachining techniques. The crystals, built using (100) silicon wafers, resulted in an upper ...
    • Reflection properties and defect formation in metallic photonic crystals 

      Özbay, Ekmel; Temelkuran, Burak; Sigalas, M.; Tuttle, G.; Soukoulis, C. M.; Ho, K. M. (IEEE, 1998-05)
      The reflection properties of layer-by-layer metallic photonic crystals were investigated using metallic photonic crystals with simple-tetragonal (st) structure. The observed properties were used to predict defect formation ...
    • Reflection properties of metallic photonic crystals 

      Temelkuran, B.; Özbay, Ekmel; Sigalas, M.; Tuttle, G.; Soukoulis, C. M.; Ho, K. M. (1998)
      We measured reflection-magnitude and reflection-phase properties of metallic photonic crystals. The experimental results are in good agreement with the theoretical calculations. We converted the reflection-phase information ...
    • Resonant cavity enhanced detectors embedded in photonic crystals 

      Temelkuran, B.; Özbay, Ekmel; Kavanaugh, J. P.; Tuttle, G.; Ho, K. M. (American Institute of Physics, 1998)
      We report a resonant cavity enhanced (RCE) detector built around a three-dimensional photonic band gap crystal. The RCE detector was built by placing a monopole antenna within the localized modes of planar and boxlike ...