Quantum Nature of Two-Dimensional Electron Gas Confinement at LaAlO3/SrTiO3 Interfaces

被引:112
作者
Janicka, Karolina [1 ]
Velev, Julian P. [1 ,2 ]
Tsymbal, Evgeny Y. [1 ]
机构
[1] Univ Nebraska, Dept Phys, Nebraska Ctr Mat & Nanosci, Lincoln, NE 68588 USA
[2] Univ Puerto Rico, Inst Funct Nanomat, Dept Phys, San Juan, PR 00931 USA
关键词
Compendex;
D O I
10.1103/PhysRevLett.102.106803
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We perform density functional calculations to understand the mechanism controlling the confinement width of the two-dimensional electron gas (2DEG) at LaAlO3/SrTiO3 interfaces. We find that the 2DEG confinement can be explained by the formation of metal induced gap states (MIGS) in the band gap of SrTiO3. These states are formed as the result of quantum-mechanical tunneling of the charge created at the interface due to electronic reconstruction. The attenuation length of the MIGS into the insulator is controlled by the lowest-decay-rate evanescent states of SrTiO3, as determined by its complex band structure. Our calculations predict that the 2DEG is confined in SrTiO3 within about 1 nm at the interface.
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页数:4
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共 35 条
[1]   Structure, stability, and electronic properties of SrTiO3/LaAlO3 and SrTiO3/SrRuO3 interfaces [J].
Albina, J. -M. ;
Mrovec, M. ;
Meyer, B. ;
Elsaesser, C. .
PHYSICAL REVIEW B, 2007, 76 (16)
[2]   BAND THEORY AND MOTT INSULATORS - HUBBARD-U INSTEAD OF STONER-I [J].
ANISIMOV, VI ;
ZAANEN, J ;
ANDERSEN, OK .
PHYSICAL REVIEW B, 1991, 44 (03) :943-954
[3]   SELF-CONSISTENT CALCULATION OF ELECTRONIC-STRUCTURE AT AN ABRUPT GAAS-GE INTERFACE [J].
BARAFF, GA ;
APPELBAUM, JA ;
HAMANN, DR .
PHYSICAL REVIEW LETTERS, 1977, 38 (05) :237-240
[4]   Mapping the spatial distribution of charge carriers in LaAlO3/SrTiO3 heterostructures [J].
Basletic, M. ;
Maurice, J. -L. ;
Carretero, C. ;
Herranz, G. ;
Copie, O. ;
Bibes, M. ;
Jacquet, E. ;
Bouzehouane, K. ;
Fusil, S. ;
Barthelemy, A. .
NATURE MATERIALS, 2008, 7 (08) :621-625
[5]   ELECTRONIC-STRUCTURE OF A METAL-INSULATOR INTERFACE [J].
BORDIER, G ;
NOGUERA, C .
SURFACE SCIENCE, 1991, 251 :457-461
[6]   Magnetic effects at the interface between non-magnetic oxides [J].
Brinkman, A. ;
Huijben, M. ;
Van Zalk, M. ;
Huijben, J. ;
Zeitler, U. ;
Maan, J. C. ;
Van der Wiel, W. G. ;
Rijnders, G. ;
Blank, D. H. A. ;
Hilgenkamp, H. .
NATURE MATERIALS, 2007, 6 (07) :493-496
[7]   POLAR HETEROJUNCTION INTERFACES [J].
HARRISON, WA ;
KRAUT, EA ;
WALDROP, JR ;
GRANT, RW .
PHYSICAL REVIEW B, 1978, 18 (08) :4402-4410
[8]   ON GENERAL THEORY OF SURFACE STATES AND SCATTERING OF ELECTRONS IN SOLIDS [J].
HEINE, V .
PROCEEDINGS OF THE PHYSICAL SOCIETY OF LONDON, 1963, 81 (520) :300-&
[9]   THEORY OF SURFACE STATES [J].
HEINE, V .
PHYSICAL REVIEW, 1965, 138 (6A) :1689-&
[10]   SOME THEORY ABOUT SURFACE STATES [J].
HEINE, V .
SURFACE SCIENCE, 1964, 2 :1-7