Tunable the kondo effect at LaAlO3/SrTiO3 interface by oxygen vacancies

Complex oxide interfaces provide a platform for the study of electrical transport properties. In this work, highquality LaAlO3/SrTiO3 heterostructures have been prepared under different oxygen partial pressure by pulsed laser deposition and monitored by in situ reflection high energy electron diffraction. Based on X-ray photoelectron spectra and resistivity measurements, it is indicated that oxygen vacancy plays a pivotal role in the Kondo effect at LaAlO3/SrTiO3 interface. The formation of Ti3+ local moments related to oxygen vacancy can be controlled by oxygen partial pressure during the deposition of LaAlO3 films. With the increase of oxygen pressure, the Kondo temperature increased from 30 K to 80 K. This work may pave the way for studying the role of oxygen vacancy in the two-dimensional electron gas at the oxide interface.

Automated summary

In this work, high-quality LaAlO3/SrTiO3 heterostructures were prepared under different oxygen partial pressure, and the role of oxygen vacancy in the Kondo effect at LaAlO3/SrTiO3 interface was investigated. It was found that the formation of Ti3+ local moments related to oxygen vacancy can be controlled by oxygen partial pressure, resulting in a change in Kondo temperature. This work paves the way for studying the two-dimensional electron gas at the oxide interface.