Magnetic Properties of LaAlO3/SrTiO3 Heterostructure Modelled on a Supercomputer

Irina Piyanzina, Volker Eyert, Thilo Kopp, Dmitrii Tayurskii


The oxide heterostructure composed of LaAlO3 (LAO) thin film on top of SrTiO3 (STO) substrate is the best known example of a system where a metallic state is formed in the STO layers next to the interface [1]. In the frame of present work we analyze an impact of oxygen vacancies and hydrogen dopants located in the AlO2 surface layer and in the TiO2 interfacial plane of LAO/STO heterostructure onto the magnetic properties by performing spin-polarized calculations based on density functional theory (DFT). We found stable local magnetic moments formed within atomically thin magnetic layers at the interface. We confirmed that agnetism can be generated by oxygen vacancies located either at the surface or at the interface. In addition, we demonstrate magnetic moments formation by hydrogen dopants located at the interface. Finally, the case of two defects combination was investigated, when negligibly small magnetic moment induction was found to take place.

Full Text:



Ohtomo A., Hwang H.Y.: A high-mobility electron gas at the LaAlO3/SrTiO3 Heterointerface. Nature 427, 423–426 (2004), DOI: 10.1038/nature02308

Pavlenko, N., Kopp, T., Tsymbal, E.Y., Mannhart, J., Sawatzky, G.A.: Oxygen vacancies at titanate interfaces: Two-dimensional magnetism and orbital reconstruction. Physical Review B 86(6), 064431 (2012), DOI: 10.1103/PhysRevB.86.064431

Michaeli, K., Potter, A.C., Lee, P.A.: Superconducting and ferromagnetic phases in SrTiO3/LaAlO3 oxide interface structures: Possibility of finite momentum pairing. Physical Review Letters 108(11), 117003 (2012), DOI: 10.1103/PhysRevLett.108.117003

Hohenberg, P., Kohn, W.: Inhomogeneous electron gas. Physical Review 136(3B), B864 (1964), DOI: 10.1103/PhysRev.136.B864

Piyanzina, I.I., Kopp T., Lysogorskiy, Y.V., Tayurskii D.A., Eyert V.: Electronic properties of LaAlO3/SrTiO3 n-type interfaces: a GGA+U study. Journal of Physics: Condensed Matter 29, 095501 (2017), DOI: 10.1088/1361-648X/aa57ac

Kresse, G., Furthmller, J.: Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Computational Materials Science 6(1), 15–50 (1996), DOI: 10.1016/0927-0256(96)00008-0

Piyanzina, I.I., Lysogorskiy, Y.V., Varlamova, I.I., Kiiamov A.G., Kopp T., Eyert V., Nedopekin O.V., Tayurskii D.A.: Analysis of electronic and structural properties of surfaces and interfaces based on LaAlO3 and SrTiO3. Journal of Low Temperature Physics 185, 597–602 (2016), DOI: 10.1007/s10909-016-1483-2

Piyanzina, I.I., Eyert V., Lysogosrkiy Yu.V., Tayurskii D.A, and Kopp T.: Oxygen Vacancies and Hydrogen Doping in LaAlO3/SrTiO3 Heterostructures: Electronic Properties and Impact on Surface and Interface Reconstruction. arXiv:1803.01382 [cond-mat.str-el] (2018),

Publishing Center of South Ural State University (454080, Lenin prospekt, 76, Chelyabinsk, Russia)