Tuning the conductivity of LaMnO$_{3}$/SrTiO$_{3}$ superlattices by stacking

First-principles density-functional-theory calculations have been applied to study the structure and electronic properties of ultrathin LaMnO$_{3}$/SrTiO$_{3}$ superlattices. We predict that upon the change of stacking, antiferromagnetic LaMnO$_{3}$/SrTiO$_{3}$ superlattices can be tuned from non-conducting insulator to conducting metal. The corresponding microscopic structure change in the superlattices is also analyzed. We find that the metal-insulator transition is accompanied by a corresponding reduction/disappearance of the Jahn-Teller (JT) distortion in the LaMnO$_{3}$ layer. The findings of this work illustrate the role of the JT distortion in the conductivity of transition-metal perovskites, and also suggest a new method for tuning metal-insulator transitions for functional device design.