Strain-induced crossover of the metal-insulator transition in perovskite manganites

Abstract

The essential role of strain in determining the electronic states of perovskite manganites is clearly demonstrated in the form of anisotropic and substrate-dependent crossover of a first-order phase transition in charge-orbital ordered epitaxial thin films of ${\left({\mathrm{Nd}}_{1-x}{\mathrm{Pr}}_x\right)}_{0.5}{\mathrm{Sr}}_{0.5}{\mathrm{MnO}}_3$. An application of (110)-oriented epitaxial growth technique allows the structural flexibility indispensable for the large anisotropic lattice deformation at the first-order transition. The technique enables us to fine-tune the Jahn-Teller distortion for manipulating the metal-insulator transition in thin films, a first step toward the strongly correlated electron devices.