Structural effect of LaAlO 3 /SrTiO 3 interface on electronic properties: Ab-initio calculations

The structural aspects of LaAlO 3 /SrTiO 3 heterostructure were investigated in detail to explain the electronic properties of interface. Cell volume change, atomic displacements were calculated for the (1×1) LaAlO 3 (m unit cells, m=3, 5)/SrTiO 3 (4 unit cells) system using ab-initio method. Both of LaAlO 3 and SrTiO 3 cells were stretched in longitudinal directions. The oxygen atoms in the cells moved to n-type interface and the movement, consequently, could be interred to contribute the conductivity of n-type interface.