Interplay between crystallographic orientation and electric transport properties in La2/3Sr1/3MnO3 films

The effect of crystallographic interface orientation on the electric transport properties of fully strained La2/3Sr1/3MnO3 films grown onto LaAlO3 substrates has been investigated. It is found that, relative to the (001) orientation, the (110) orientation strongly enhances the transport properties for film thickness in the range between 3 and 12 nm. Such an effect was ascribed to reduced [relative to the (001) substrates] tetragonal distortion induced by epitaxy onto (110)-oriented substrates. The reduced tetragonal distortion quenches the occupational imbalance between the Mn e(g) orbitals thus, ultimately, reinforcing the ferromagnetic double exchange transport mechanism.