  Complex oxide thin films and heterostructures offer a wide range of
properties originating from the intrinsic coupling between lattice strain and
magnetic/electronic ordering. This article reviews experimental,
phenomenological, and theoretical analyses of the coupling of strain with
electronic and magnetic properties of mixed valence manganite heterostructures.
The influence of epitaxial strain on the magnetic properties of manganite films
is measured using macroscopic magnetization measurements and shown mixed
reports suggesting, both, an increase and decrease in ferromagnetic phases on
the application of the strain. Using polarized neutron reflectivity (PNR), a
simultaneous measurement of transport and magnetic properties of manganite thin
films showed direct evidence of modification in the magnetic properties on the
application of bending strain. The coupling coefficient of strain and magnetism
of manganite heterostructures was estimated using PNR, which not only helped to
understand the correlation of elastic strain with magnetism but also explained
the condition of magnetic phase order change in the phase-separated systems
within a phenomenological Ginzburg Landau theory. An overview is also provided
of the current perspectives and existing studies on the influence of strain on
structure, electronic, magnetic, magnetic anisotropy, phase coexistence and
magnetocaloric properties of mixed valence manganite heterostructures. Based on
the understanding of a diverse range of perovskite functionalities, detailed
perspectives on how the coupling of strain and magnetism open up pathways
toward the emergence of novel device design features including the different
ways of applying uniform strain, are discussed.
