Influence of Lattice Strain on Phase Separation and Percolative Behaviors in La0.325Pr0.3Ca0.375 MnO3 Thin Films.

The compressive and tensile strains induced by different substrates on La0.325Pr0.3Ca0.375MnO3 (LPCMO) thin films have been investigated. It is found that the in-plane compressive strain favors the ferromagnetic metallic phase by increasing the hopping amplitude between neighboring elections and decreasing the tilt of the MnO6 octahedron, leading to the weakening of the phase separation. On the other hand, the in-plane tensile strain in films prefers to increase the stability of long-range charge/orbital ordering (COO) phase. Under 5 T magnetic field, the 30 nm LPCMO films on NGO and LSAT substrates show an obvious metal–insulator transition, indicating that the COO phase can be melted by the magnetic field at low temperature in the film with small in-plane tensile strain. The LPCMO film on STO substrate keeps insulating in the entire measuring temperature range even under 5 T magnetic field, suggesting that the COO phase in the film with a large tensile strain is more robust. [ABSTRACT FROM AUTHOR]