Thickness-dependent magnetotransport properties of La0.6Sr0.2Mn1.2O3 films on SrTiO3 and LaAlO3 substrates

Electric and magnetoresistive properties of La
0.6S
r
0.2
Mn
1.2
O
3
films deposited on SrTiO
3
(001) and LaAlO
3
(001) single crystalline substrates by magnetron sputtering have been studied. Characteristic features of the evolution of resistivity, magnetoresistance and Curie temperature upon the decrease of film thickness from 500 to 12.5 nm are specified. A key role of a thin strained layer adjacent to the substrate is demonstrated. The critical thicknesses of the strained layer are calculated for the films deposited on different substrates.