RbH_2PO_4不同相的铁电性和光学特性(英文)  

The ferroelectricity and optical properties of different phases of RbH_2PO_4

作　　者：韩红培[1] 徐斌[2] 余功奇[3] 张现周[4] 孙金峰[4] 

机构地区：[1]许昌学院电气信息工程学院,许昌461000 [2]华北水利水电学院数信学院,郑州450011 [3]第二炮兵指挥学院,武汉430012 [4]河南师范大学物理与信息工程学院,新乡453007

出　　处：《原子与分子物理学报》2009年第5期909-914,共6页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(10574039);河南省自然科学基金(2009B140008)

摘　　要：利用第一性原理系统地研究了RbH_2PO_4晶格优化结构、总的和分的态密度、电荷密度分布.我们发现氧原子和Rb,H原子的杂化形成了两种离子群,在铁电相离子键和PO_4四面体的耦合强度比顺电相更强.结果,通过P-O和H-O的距离改变电荷密度的再分布和PO_4四面体的顺序旋转导致了铁电性的产生.两种类型粒子群的运动和自动成型畴壁导致了可以观测的焦热电流.First-principles calculations are performed for the study of RbH2PO4 with the lattice optimized structure, Electronic bands, total and partial densities of states as well as charge density distribution are analyzed systematically. It is noted that oxygen atomic hybridize with Rb,and H,there exist two-type ionic groups. The couple strength between the cation bonds and the PO4 tetrahedra in the ferroelectric phase is stronger than that in the paraelectric phase. As a result, the redistribution of charge density by change of P-O and H-O distance and the subsequent rotaticns of the PO4 texrahedra can lead to the driving force of the ferroelectric behaviors. The motion of two-type ionic groups,relating to atomically shape domain walls,can lead to the measurable pyroelectric current.

关 键 词：铁电体 电子带结构 态密度 

分 类 号：O469[理学—凝聚态物理]