Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2024Scopus SJRQ2/r/bayburt/12884
  A Dual-Band Terahertz Metamaterial Absorber Using an All-Metal Aluminum Hexagonal Metasurface Structure for Sensing of Cancerous Cells

  Teber, Ahmet

  This article proposes a dual-band terahertz metamaterial absorber (TMA) where all components of the designed structure are made of aluminum (optical) material. Unlike the metal-dielectric-metal structures typically found in the literature, the proposed structure has a lightweight material that does not contain a sandwich structure. Thus, the structure greatly simplifies the production process and reduces the cost. The results of electromagnetic and equivalent circuit simulations are compared based on the S11 parameters (in dB), resulting in good agreement of findings by CST and ADS, respectively. The proposed TMA operates in dual frequency bands at 1.902 THz (f1) and 1.976 THz (f2), with strong absorption of 98.17% and 99.05%, respectively. The quality factors (Q-factors) corresponding to these resonant frequencies are 240.15, (f1) and 181.61, (f2). When the refractive index (RI) of the medium surrounding the TMA varies, the absorption peaks shift accordingly. The detection properties of the proposed TMA are examined as the RI of the surrounding medium is varied primarily between 1.34 and 1.39 with an increase of 0.01 for biomedical applications. The corresponding sensitivities of two resonance peaks are 0.794 THz/RIU and 0.971 THz/RIU, respectively. Since many samples, such as human blood, basal/breast/cervical cells, and cancerous cells, are found in this RI range, the proposed TMA sensor can be used as a viable biosensor in the identification of biological samples for real-world applications. Graphical Abstract: (Figure presented.)

  AtıfScopus36·WoS31·OpenAlex37

  İncele
• Derleme MakaleAçık Erişim2019Scopus SJRQ2/r/bayburt/13886
  Thermoelectric Coolers (TECs): From Theory to Practice

  Guclu, Tamer; Cuce, Erdem

  Thermoelectric coolers (TECs) are solid state units, which provide reliable energy conversion with no noise or vibration. They are also lightweight and do not include any moving parts. The current coefficient of performance (COP) range of TECs has shown a trend of improvement, and TECs have a wide range of usage areas. Within the scope of this research, TECs are comprehensively evaluated in terms of several aspects such as type, material, design, modelling, thermal performance, potential applications, economic and environmental issues. It can be achieved through the results that the COP of TECs is highly dependent on the temperature difference between hot and cold side (ΔT), and maximum COP is obtained when ΔT is close to zero. It is also observed that COP can be enhanced by more than 55% when the hot side is thermally regulated by phase change materials (PCMs) or integrated with a water cooling unit.

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  AtıfScopus69·WoS61·OpenAlex76

  İncele
• MakaleYalnız künye2017Scopus SJRQ2/r/bayburt/13746
  Optical and Surface Characteristics of Mg-Doped GaAs Nanocrystalline Thin Film Deposited by Thermionic Vacuum Arc Technique

  Pat, Suat; Özen, Soner; Şenay, Volkan; Korkmaz, Şadan

  Magnesium (Mg) is the most promising p-type dopant for gallium arsenide (GaAs) semiconductor technology. Mg-doped GaAs nanocrystalline thin film has been deposited at room temperature by the thermionic vacuum arc technique, a rapid deposition method for production of doped GaAs material. The microstructure and surface and optical properties of the deposited sample were investigated by x-ray diffraction analysis, scanning electron microscopy, energy-dispersive x-ray spectroscopy, atomic force microscopy, ultraviolet–visible spectrophotometry, and interferometry. The crystalline direction of the deposited sample was determined to be (220) plane and (331) plane at 44.53° and 72.30°, respectively. The Mg-doped GaAs nanocrystalline sample showed high transmittance.

  AtıfScopus19·WoS5·OpenAlex59

  İncele
• MakaleAçık Erişim2016Scopus SJRQ2/r/bayburt/14176
  Surface, Nanomechanical, and Optical Properties of Mo-Doped GeGaAs Thin Film Deposited by Thermionic Vacuum Arc

  Pat, Suat; Senay, Volkan; Özen, Soner; Korkmaz, Sadan

  Mo-doped and undoped GeGaAs layers have been deposited by the thermionic vacuum arc (TVA) method, an alternative, fast plasma deposition technique. The thicknesses of the deposited layers were identical. The surface, mechanical, and optical properties of the deposited layers were studied to determine the influence of Mo doping on GeGaAs. The transparency of GeGaAs was shifted towards the near-infrared region by Mo doping. Bandgap values shifted by approximately 0.3 eV. In other words, the bandgap value of Mo-doped GeGaAs was nearly equal to that of GaAs materials. The average roughness and grain size of the Mo-doped material were smaller than for the GeGaAs layer. The particle distributions of the Mo-doped and undoped GeGaAs were almost perfect Gaussians. However, the mean height of the Mo-doped GeGaAs grains was six times that for undoped GeGaAs. The surface was homogeneous. The Mo-doped layer showed greater absorbance than the GeGaAs material. The produced Mo-doped sample showed hybrid properties.

  AtıfWoS1·OpenAlex1

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