The Distinct Effects of Homogeneous Weak Disorder and Dilute Strong Scatterers on Phase Competetion in the Manganites

Abstract

We study the two orbital double-exchange model in two dimensions in the presence of antiferromagnetic (AF) superexchange, strong Jahn-Teller coupling, and substitutional disorder. At hole doping x=0.5 we explore the `bicritical' regime where the energy of a ferromagnetic metal and a charge and orbital ordered (CO-OO) CE state are closely balanced, and compare the impact of weak homogeneous disorder to that of a low density of strong scatterers. Even moderate homogeneous disorder suppresses the CE-CO-OO phase and leads to a glass with nanoscale correlations. Dilute strong scatterers of comparable strength, however, convert the CE-CO-OO phase to a phase separated state with ferromagnetic and AF-CO-OO clusters. We provide the first spatial description of these phenomena and compare our results in detail to experiments on the half-doped manganites.

4 pages pdflatex, 4 jpg figs, published

References in corpus (3)

• Competing Orders and Disorder-induced Insulator to Metal Transition in Manganites
• Jahn-Teller distortion induced charge-ordering in CE phase of manganites
• Fragility of the A-type AF and CE Phases of Manganites: An Exotic Insulator-to-Metal Transition Induced by Quenched Disorder

Cited by in corpus (7)

• Ferromagnetic tendency at the surface of CE charge-ordered manganites
• Multicritical end-point of the first-order ferromagnetic transition in colossal magnetoresistive manganites
• The Influence of A-site Ionic Radii on the Magnetic Structure of Charge Ordered La0.5Ca0.5-xSrxMnO3 Manganites
• Non-magnetic B-site Impurities Induce Ferromagnetic Tendencies in CE Manganites
• Exploiting B Site Disorder for Phase Control in the Manganites
• Dopant-dependent impact of Mn-site doping on the critical-state manganites: R0.6Sr0.4MnO3 (R=La, Nd, Sm, and Gd)
• Disorder-induced orbital ordering in doped manganites