The polycrystalline ceramic Pb0.5Ba1.5BiVO6 manifesting the complex double perovskite structure was tailored by the conventional solid state route at a moderate temperature.Qualitative phase analysis and formation of ...The polycrystalline ceramic Pb0.5Ba1.5BiVO6 manifesting the complex double perovskite structure was tailored by the conventional solid state route at a moderate temperature.Qualitative phase analysis and formation of the ceramic were affirmed by XRD analysis.The X-ray powder diffraction pattern of the compound explored at room temperature affirms the single phase formation with double perovskite structure exhibiting rhombohedral phase.Microstructural analysis of the studied compound procured from the Scanning Electron Microscope(SEM)validates the formation of dense microstructures and nonuniformly distributed grains with minimal voids.Compositional analysis was shaped through the Electron Diffraction Spectroscopy(EDS)confirming the absence of con-tamination of any other metals apart from the mentioned ones.Dielectric(Cr and tanδ)parameters of the compound were studied using the LCR analyzer at different temperatures and wide range of frequencies.The polarization and dielectric study affirms the presence of ferroelectricity in the material with transition temperature much above the room temperature.The tangent dielectric loss of this sample being almost minimal at room temperature attributes it to find applications in different grounds of electronics.Optical equities of the ceramic were further analyzed by the RAMAN,FTIR,UV–Vis and Photoluminescence spectroscopy.展开更多
A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices（TEDs）,namely a Gunn diode and an impact avalanche transit time（IMPATT） device.Microwave ch...A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices（TEDs）,namely a Gunn diode and an impact avalanche transit time（IMPATT） device.Microwave characteristics such as device efficiency and the microwave power generated are computed and compared at D-band（140 GHz center frequency） to see the potentiality of each device under the same operating conditions.It is seen that GaN-based IMPATT devices surpass the Gunn diode in the said frequency region.展开更多
文摘The polycrystalline ceramic Pb0.5Ba1.5BiVO6 manifesting the complex double perovskite structure was tailored by the conventional solid state route at a moderate temperature.Qualitative phase analysis and formation of the ceramic were affirmed by XRD analysis.The X-ray powder diffraction pattern of the compound explored at room temperature affirms the single phase formation with double perovskite structure exhibiting rhombohedral phase.Microstructural analysis of the studied compound procured from the Scanning Electron Microscope(SEM)validates the formation of dense microstructures and nonuniformly distributed grains with minimal voids.Compositional analysis was shaped through the Electron Diffraction Spectroscopy(EDS)confirming the absence of con-tamination of any other metals apart from the mentioned ones.Dielectric(Cr and tanδ)parameters of the compound were studied using the LCR analyzer at different temperatures and wide range of frequencies.The polarization and dielectric study affirms the presence of ferroelectricity in the material with transition temperature much above the room temperature.The tangent dielectric loss of this sample being almost minimal at room temperature attributes it to find applications in different grounds of electronics.Optical equities of the ceramic were further analyzed by the RAMAN,FTIR,UV–Vis and Photoluminescence spectroscopy.
基金Project supported by the Department of Science and TechnologyGovernment of India through SERC,FIST and TIFAC Program
文摘A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices（TEDs）,namely a Gunn diode and an impact avalanche transit time（IMPATT） device.Microwave characteristics such as device efficiency and the microwave power generated are computed and compared at D-band（140 GHz center frequency） to see the potentiality of each device under the same operating conditions.It is seen that GaN-based IMPATT devices surpass the Gunn diode in the said frequency region.
