Superconductivity in the Two-Dimensional Electron Gas at Transition Metal Oxide Interfaces

  • J. C. NieEmail author


The transition metal oxide interface has attracted extensive attention due to its unique, strong correlation properties. In particular, LaAlO3/SrTiO3(LAO/STO) interface has a high mobility of two-dimensional electron gas (2DEG) and specific physical phenomena such as superconductivity, ferromagnetism, and the coexistence of superconductivity and ferromagnetism are observed. Other transition metal oxide interface systems also show high mobility and similar novel quantum phenomena. Superconducting 2DEG at the LAO/STO interface offers an appealing platform for quantum phase transition from a superconductor to a weakly localized metal. Although the research on the transition metal oxide interface is extensive, there are still many outstanding unsolved issues, such as the origin of 2DEG, the superconducting pairing mechanism of 2DEG, the origin of ferromagnetism, and the coexistence of superconductivity and ferromagnetism. Considering these aspects, the 2DEG of the transition metal oxide interface is of high interest for basic research and potential applications. This chapter presents a brief state-of-the-art view of the research results on superconductivity in 2DEG based on literature and our findings.


Transition metal oxide interface LaAlO3/SrTiO3 heterojunction Two-dimensional electron gas (2DEG) Superconductivity Interface superconductivity Ferromagnetism Coexistence of superconductivity and ferromagnetism Superconducting pairing mechanism Unconventional superconductivity p-wave superconductor Spin-triplet pairing FFLO superconductor Superconductor-insulator/metal transition 



This work is supported by the National Natural Science Foundation of China (Grants No. 11674031 and No. 11474022) and the National Basic Research Program of China (Grants No. 2014CB920903 and No. 2013CB921701) for the financial support.


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Authors and Affiliations

  1. 1.Department of PhysicsBeijing Normal UniversityBeijingPeople’s Republic of China

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