First-principles study of metal-induced gap states in metal/oxide interfaces and their relation with the complex band structure

摘要

We develop a simple model to compute the energy-dependent decay factors ofmetal-induced gap states in metal/insulator interfaces considering thecollective behaviour of all the bulk complex bands in the gap of the insulator.The agreement between the penetration length obtained from the model(considering only bulk properties) and full first-principles simulations of theinterface (including explicitly the interfaces) is good. The influence of theelectrodes and the polarization of the insulator is analyzed. The methodsimplifies the process of screening materials to be used in Schootky barriersor in the design of giant tunneling electroresistance and magnetoresistancedevices.