用基于密度泛函理论的第一性原理方法研究了在A lS b （110）衬底表面外延生长1～6层Bi薄膜的能带结构，计算了它们的带隙。研究发现，不同厚度的Bi薄膜显示出传导性质的奇偶振荡，1层和3层显示出非金属性质，2层和4层及更高的层数转变...用基于密度泛函理论的第一性原理方法研究了在A lS b （110）衬底表面外延生长1～6层Bi薄膜的能带结构，计算了它们的带隙。研究发现，不同厚度的Bi薄膜显示出传导性质的奇偶振荡，1层和3层显示出非金属性质，2层和4层及更高的层数转变为金属性质。展开更多
The electro,tic, magnetic, and ferroelectric properties of BiCrO3 in C2/c and R3c structure are investigated by first principles calculations. It is found that the easy magnetization axis in C2/c structure is along th...The electro,tic, magnetic, and ferroelectric properties of BiCrO3 in C2/c and R3c structure are investigated by first principles calculations. It is found that the easy magnetization axis in C2/c structure is along the b axis, the magnetic order in R3c structure is G-type antiferromagnetic and the easy magnetization axis is along the rhombohedral [111] direction. Berry phase theory predicts that the R3c structure of BiCrOa has a large spontaneous polarization of 73.9 μC/cm2 along the rhombohedral [111] direction.展开更多
基金Supported by the Special Funds of the National Natural Science Foundation of China under Grant No 11347187, the National Natural Science Foundation of China under Grant No 11404058, the Science and Technology Research Program of Henan Province of China under Grant No 132102210141, and the Doctoral Program of Henan Institute of Engineering under Grant No D2013007.
文摘The electro,tic, magnetic, and ferroelectric properties of BiCrO3 in C2/c and R3c structure are investigated by first principles calculations. It is found that the easy magnetization axis in C2/c structure is along the b axis, the magnetic order in R3c structure is G-type antiferromagnetic and the easy magnetization axis is along the rhombohedral [111] direction. Berry phase theory predicts that the R3c structure of BiCrOa has a large spontaneous polarization of 73.9 μC/cm2 along the rhombohedral [111] direction.
