标题:
第一性原理研究(Pb1-xSrx)TiO3磁性以及氧空位对其磁性的影响The Magnetism of (Pb1-xSrx)TiO3 and the Effect of Oxygen Vacancy on Its Magnetism by First-Principles Study
作者:
林志萍, 段鹤, 张欣
关键字:
第一性原理, 铁电材料, 氧空位, 铁磁性First-Principles, Ferroelectric Materials, Oxygen Vacancy, Ferromagnetism
期刊名称:
《Advances in Condensed Matter Physics》, Vol.5 No.3, 2016-08-25
摘要:
本文采用基于密度泛函理论的广义梯度近似方法和赝势平面波法的第一性原理计算讨论了PbTiO3体系的氧的化学势范围、(Pb1−xSrx)TiO3体系的磁性以及氧空位对该体系磁性的影响。结果表明，有Sr掺杂的情况下，(Pb1−xSrx)TiO3体系呈现了一定的弱铁磁性(x = 0.5时的最大磁矩小于0.04μB/unitcell)；当存在氧空位时，(Pb1−xSrx)TiO3体系具有铁磁性，磁矩为0.486μB/vacancy 和未掺杂的PbTiO3中由于氧空位的存在而产生的磁矩0.488μB/vacancy 一致。
Based on first-principles calculation, it is discussed for the chemical potential regions of oxygen of PbTiO3 system under the thermodynamics equilibrium conditions, the magnetism of (Pb1−xSrx)TiO3 and the effect of oxygen vacancy on the magnetism of (Pb1−xSrx)TiO3. Results displays that increasing Sr, (Pb1−xSrx)TiO3 appears the weak ferromagnetism (and when x = 0.5, the maximum magnetic moment is less than 0.04μB/unitcell). If there is a oxygen vacancy in (Pb1−xSrx)TiO3 system, it takes on the ferromagnetism and magnetic moment is 0.486μB/vacancy , which is agreement with the magnetic moment 0.488μB/vacancy of pure PbTiO3 system with oxygen vacancy.