Exploiting B-site disorder for phase control in the manganitesKalpataru Pradhan, Anamitra Mukherjee and Pinaki Majumdar
Harish-Chandra Research Institute - Chhatnag Road, Jhusi, Allahabad 211019, India
received 10 July 2008; accepted in final form 24 September 2008; published November 2008
published online 30 October 2008
Disorder on the active d element site is usually very disruptive for conduction and long-range order in perovskite transition metal oxides. However, in the background of phase competition such “B-site” dopants also act to promote one ordered phase at the expense of another. This occurs either through valence change of the transition metal or via creation of “defects” in the parent magnetic state. We provide a framework for understanding the complex variety of phenomena observed in B-sitedoped manganites and identify the key parameters that control the physics. Using a spatially resolved analysis of B ions in various manganite phases we explain the existing data and predict new situations where highly polarisable phase separated states can be created.
75.47.Lx - Manganites.
75.47.Gk - Colossal magnetoresistance.
72.80.Ng - Disordered solids.
© EPLA 2008