Phonon calculations on microwave dielectric material La2/3TiO3-LaAlO3: Density-Functional Perturbation Theory Study

• Main Authors: Chi-Nan, Lin, 林植南
• Other Authors: 林諭男
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/55429704024942822189

碩士 === 淡江大學 === 物理學系碩士班 === 97 === At the present, the combination of high performance computation and solid-state theory provides a promising methodology to elucidate the microscopic properties of versatile materials. We use the first-principles to start the simulation on the microwave dielectric material La2/3TiO3 - LaAlO3. At first, we get the La2/3TiO3 crystal structure from the atomic position of ceramic 0.9La2/3TiO3-0.1LaAlO3 , and then we use the Density - Functional Perturbation Theory to investigate the phonons at Γ point. According to the phonon calculation, the calculated eigenvalues and the corresponding eigenvectors of each vibrational mode at Γ point provide a great help on our experimental observations. Comparing with Raman and FTIR spectrum, we can study the dielectric properties on the microwave dielectric material La2/3TiO3 - LaAlO3.