| Summary: | 碩士 === 國立高雄師範大學 === 物理學系 === 96 === Abstract
During the past decades, material technology has being developed rapidly and attracted much attention because of the widespread industrial application in electronic
devices and etc.
In this thesis, we perform the density-functional calculations of the atomic, electronic, magnetic properties of RMnO3 (R = Ho, Er, Tm and Lu) in pervoskite structures. It is found that these late-R magnenates under high pressure conditions exist the so-called anti-ferromagnetic E-type configuration, accompanied by the spontaneous polarization. Because of ferroelectric and magnetic order, we also try to find the correlations of lattice distortions and magnetic polarizations. Further more, we discuss the interplay between this special spin phase and the lattice distortion using the double-exchange mechanism and Jahn-Teller distortion. A pretty matched
agreement is reached.
Finally, we also investigate the associated calculations with and without the inclusion of the strong electron-electron correlation U. The resultant calculations show that the consideration of such kind of correlation makes little improvements on
the corresponding properties of these compounds interested here.
|
|---|
