Search for dissertations about: "band gap engineering"

Showing result 1 - 5 of 115 swedish dissertations containing the words band gap engineering.

2. 1. Slot Array Antennas at V-band based on Inverted Microstrip Gap Waveguide

   Author : Jinlin Liu; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; inverted microstrip gap waveguide; metallic pins; perfect magnetic conductor; slots array and variational method;

   Abstract : Recently, gap waveguide technology is introduced as a proper guiding structure for millimeter-systems. The conception of gap waveguide technology can be modeled for theoretical analysis by two parallel plates, a top perfect electric conductor layer and a bottom perfect magnetic conductor layer. READ MORE

4. 2. Millimeter-Waves Slot Array Antennas based on Gap Waveguide Technology

   Author : Jinlin Liu; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Recently, gap waveguide technology is introduced as a promising guiding structure for millimeter-wave systems. The conception of gap waveguide technology can be modeled for theoretical analysis by two parallel plates, a top perfect electric conductor layer and a bottom perfect magnetic conductor layer. READ MORE

5. 3. Towards Gap Waveguide Array Antenna for Millimeter Wave Applications

   Author : Abbas Vosoogh; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gap waveguide; Electric Discharge Machining EDM ; Artificial Magnetic Conductor AMC ; slot array antenna; low sidelobe; high effciency; millimeter wave; aperture efficiency; Bandpass filter BPF ;

   Abstract : The millimeter wave frequency range has got a lot of attention over the past few years because it contains unused frequency spectrum resources that are suitable for delivering Gbit/s end-user access in areas with high user density. Due to the limited output power that current RF active components can deliver in millimeter waves, antennas with the merits of low profile, high gain, high effciency and low cost are needed to compensate free space path loss and increase the communication distance for the emerging high data rate wireless systems. READ MORE

6. 4. Modelling Band Gap Gradients and Cd-free Buffer Layers in Cu(In,Ga)Se2 Solar Cells

   Author : Jonas Pettersson; Charlotte Platzer-Björkman; Marika Edoff; Marc Burgelman; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; CIGS; Thin film solar cells; Electrical modelling; Alternative buffer layers; Gallium gradients; Simulations; Electrical characterization; Metastabilities; Light-soaking; Hall measurements; Persistent photoconductivity; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

   Abstract : A deeper understanding of Cu(In,Ga)Se2 (CIGS) solar cells is important for the further improvement of these devices. This thesis is focused on the use of electrical modelling as a tool for pursuing this aim. Finished devices and individual layers are characterized and the acquired data are used as input in the simulations. READ MORE

7. 5. Band gap engineering in Cu2ZnGexSn1-xS4 thin film solar cells

   Author : Nishant Saini; Charlotte Platzer-Bjorkman; Jes K Larsen; Edgardo Saucedo; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CZTS; CZGTS; bandgap grading; ZTO; KCN-etching; titanium nitride; solar cell; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

   Abstract : Photovoltaics based on kesterite Cu2ZnSnS4 (CZTS) has attracted interest as a sustainable alternative to other thin film technologies due to their tunable material properties and earth-abundance. However, the efficiency is limited to 12. READ MORE