1. Oxide Heterostructure
Shuhua Liang
UTK Physics Dept.

2. Perovskite Stucture ABO3

3. LCMO (magnetic material) La0.67Ca0.33MnO3

4. High Tc Superconductor Lattice
LSCO (High Tc Sc)
(La1-xSrxCuO3 )

5. YBCO High Tc Sc YBa2Cu3O7-x CuO2 Plane More layers Higher Tc Distance
Carriers in CuO2 Plane

6. Metallic Interfaces between Insulators
LaTiO3 layers (bright) of varying thickness spaced by 5 layers of SrTiO3

7. LaTiO3
La 3+ one more e
Ti 3+
Mott insulator
A=0.397nm
SrTiO3
Sr 2+
Ti 4+
Band insulator
A=0.391nm

8. Charge leakage
the Ti3+ signal is considerably wider than that of the La
“Ti3+”~extra electron
The ‘tail’ of Ti3+ have a decay length of 1nm as an order of screening length!

9. Metallic Structure
Fraction of Ti3+ is a function of the number of LaTiO3 unit cells.
Conductivity is a function of the thickness of LaTi3 and SrTi3

10. CMR
Colossal magnetoresistance

11. LaMnO3

12. Double-exchange mechanism
Ca 2+ cause electron free to move.

13. Oxide heterostructure interface

14. Ferromagnetic/Sc oxide interface
Sc: YBa2Cu3O7-x
FM: La0.67Ca0.33MnO3

15. interface

16. Electrons transfer

17. Thank you!