$R$-site Randomness Effect in Double-Perovskite $R$BaMn${}_2$O${}_6$

Abstract

We have investigated the $R$-site randomness effect of $R$/Ba-ordered $R$BaMn${}_2$O${}_6$ ($R$ = rare earth) by using Y${}_{1-y}$La${}_y$BaMn${}_2$O${}_6$ (0 (\leq) $y$ (\leq) 1) in which $R$ (Y,La) and Ba are regularly arranged while Y and La randomly occupy the $R$-site. YBaMn${}_2$O${}_6$ ($y$ = 0) undergoes charge/orbital ordering (CO) transition at $T_{\mathrm{CO}}$ = 500 K while LaBaMn${}_2$O${}_6$ ($y$ = 1) shows ferromagnetic metallic (FM) behavior below 350 K\@. In 0 (\leq) $y$ (\leq) 0.6, $T_{\mathrm{CO}}$ decreases with an increase in $y$. In 0.6 (\leq) $y$ (\leq) 0.8, $R$-site randomness causes strong phase separation tendencies among the FM, antiferromagnetic (AFM), and CO insulating (COI) states. The large magnetoresistance is observed in the phase separated region.

4 pages, 2 figures, proceeding of International Conference on Magnetism 2009

References in corpus (3)

• A-site Randomness Effect on Structural and Physical Properties of Ba-based Perovskite Manganites
• Structures and Electromagnetic Properties of New Metal-Ordered Manganites; RBaMn_{2}O_{6} (R = Y and Rare Earth Elements)
• Successive Phase Transitions in a Metal-Ordered Manganite Perovskite YBaMn2O6

Cited by in corpus (1)

• muSR Investigation of magnetically ordered states in A-site ordered perovskite manganites RBaMn2O6 (R = Y and La)