Magnetic properties of R2Mn2O7 pyrochlore rare-earth solid solutions
Loading...
Access rights
openAccess
publishedVersion
URL
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
Authors
Imamura, N.
Karppinen, M.
Yamauchi, H.
Goodenough, J.B.
Date
Department
Major/Subject
Mcode
Degree programme
Language
en
Pages
1-4
Series
PHYSICAL REVIEW B, Volume 82, issue 13
Abstract
Three (R,R′)2Mn2O7 ferromagnetic pyrochlore systems were studied to investigate the role of the R3+ ionic size versus 4f moment on the magnetic properties of the Mn2O7 sublattice. The Curie temperature TC=18±1 K for R=Y and Lu remained nearly constant for (Y1−xLux)2Mn2O7 but the magnetization data show characteristics of spin-glass behavior in low magnetic fields, and at 5 T, the magnetization fails to reach the expected 3 μB/Mn4+ found by 0.5 T in Tl2Mn2O7 and In2Mn2O7. A frustrated, minor antiferromagnetic component apparently competes with the ferromagnetic component of the Mn4+-O-Mn4+ interactions to give a minor antiferromagnetic component to the major ferromagnetic spin alignment of the Mn4+ ions. A TC=42±1 K for R=Dy and Yb remains nearly constant in the (Dy1−yYby)2Mn2O7 system and TC increases systematically from 19 to 42 K with Dy concentration in (Dy1−zLuz)2Mn2O7, which clearly shows that a ferromagnetic interaction between the R3+-ion and Mn4+-ion spins favors ferromagnetic alignment of the Mn4+-ion spins to double the magnitude of TC by relieving the frustration of the Mn2O7 sublattice. The R3+-ion size has little effect as the Mn-O-Mn bond angle changes by no more than ∼1° with changing ionic radius of the R3+ ion.Description
Keywords
Other note
Citation
Imamura , N , Karppinen , M , Yamauchi , H & Goodenough , J B 2010 , ' Magnetic properties of R2Mn2O7 pyrochlore rare-earth solid solutions ' , Physical Review B , vol. 82 , no. 13 , 132407 , pp. 1-4 . https://doi.org/10.1103/PhysRevB.82.132407