Thickness dependent structural and magnetic properties of Nd2NiMnO6 epitaxial thin films

The structural and magnetic properties of epitaxial Nd2NiMnO6 (NNMO) thin films with varying thickness have been investigated. NNMO thin films of thickness ranging from 60 to 300 nm were deposited onto (001) oriented SrTiO3 substrate by pulsed laser deposition technique. The X-ray diffraction and Raman scattering analysis confirm that all films have c-axis epitaxial growth with orthorhombic structure and films having smaller thickness (< 180 nm) were under tensile strain. The Raman spectra suggest that critical thickness for strain relaxation lies between 90 and 180 nm. The magnetic measurements suggest a strong dependence of magnetic properties on the present strain in the films. The ferromagnetic transition temperature (TC) and saturation magnetization were found to increase with increasing film thickness. The film with thickness of 300 nm exhibits the highest saturation magnetization (~ 3.5 × 105 A/m) with a Curie temperature (TC) of 200 K, which is higher than the bulk TC of NNMO compound.