Hasil Pencarian  ::  Simpan CSV :: Kembali

"Kebutuhan akan divais optik terus mengalami peningkatan yang cukup pesat belakangan ini. Material Gallium Nitride merupakan material yang menarik banyak peneliti, karena memiliki beberapa kelebihan, antara lain: stabil terhadap perubahan suhu, memiliki tingkat epitaxial growth yang tinggi, konsumsi daya yang rendah dan memiliki direct band gap yang tinggi. Namun riset dibidang passive waveguide hingga kini belum banyak ditekuni para peneliti. Oleh karena itu, pada skripsi ini, dikembangkan power splitter dengan rugi-rugi yang rendah dan memiliki distribusi medan optik yang uniform, dengan memanfaatkan bentuk pandu gelombang S-Bend. Desain Y-branch power splitter dilakukan dengan menggunakan OptiBPM 12 free trial. Dari hasil simulasi diperoleh Y-branch power splitter terbaik saat tebal dan lebar pandu gelombang lurus adalah 4 μm, panjang pandu gelombang multimode sebesar 25 μm dan radius pandu gelombang S-Bend 10,5 μm.

---

Recently, demand of optical devices are growing termendously, Gallium Nitride is become attractive by many researchers, because of its advantages, such as: temperature stability, high rate of epitaxial growth, low power consumption and large direct band gap. But nowadays, there is not much research about passive waveguide GaN based. Thats why, this final project of Y-branch power splitter which has low power consumption and uniformity of distribution optical waveguides distribution using S-Bend waveguides is designed. OptiBPM 12 free trial is used for the design purpose in this final project. From the simulation, it can be concluded that the best S-Bend Y-branch power splitter is when straight waveguide both thickness and width are 4 μm, multimode waveguide length is 25 μm and radius of S-Bend is 10,5 μm."

"The electronic and optical properties of a-Al2O3 after induced by 3-keV Ar+ sputtering have been studied quantitatively by use of reflection electron energy loss spectroscopy (REELS) spectra. The band gap values of a-Al2O3 was determined from the onset values of the energy loss spectrum to the background level of REELS spectra as a function of time Ar+ bombardment. The bandgap changes from 8.4 eV before sputtering to 6.2 eV after 4 minutes of sputtering.The optical properties of α-Al2O3 thin films have been determined by comparing the experimental cross section obtained from reflection electron energy loss spectroscopy with the theoretical inelastic scattering cross section, deduced from the simulated energy loss function (ELF) by using QUEELS-ε(k)-REELS software. The peak assignments are based on ELF and compared with reported data on the electronic structure of α-Al2O3 obtained using different techniques. The results demonstrate that the electronic and optical properties before and after surface reduction will provide further understanding in the fundamental properties of α-Al2O3 which will be useful in the design, modeling and analysis of devices applications performance."