Magnetic and electric "dead" layers in (La0.7Sr0.3)MnO3 thin films

The magnetic, transport, and structural properties of (La0.1Sr0.3)MnO3 films deposited on MgO (001) are reported as a function of thickness and substrate temperature. The substrate temperature is fundamental in determining the structural properties and a deviation from the optimum temperature (680 degreesC) leads to grain boundaries and an imperfect (001) texture. Films with different thicknesses were deposited at the optimum deposition temperature. Magnetization and resistivity measurements on these films are interpreted in terms of magnetic and electric "dead" layers. The electric dead layer is an insulating layer approximately 4 nm thick while the magnetic dead layer is a region of weakly coupled noncollinear spins approximately 10 nm thick at each interface. (C) 2001 American Institute of Physics.