The magnetic phase diagram of La2-2cursive Greek chiSr1+2cursive Greek chiMn2O7 (0.30 ≤ cursive Greek chi ≤ 0.50) was reexamined from the point of view of the crystal structure, particularly the Jahn-Teller (JT) distortion ΔJT of Mn-O6 octahedra, i.e., the ratio of the averaged apical Mn-O bond length to the equatorial Mn-O bond length. We have found that ΔJT decreases with increasing hole concentration cursive Greek chi, while the canting angle between neighboring planes continuously increases from 0° (planar ferromagnet: 0.32 ≤ cursive Greek chi ≤ 0.38) to 180° (A-type antiferromagnet (AFM): cursive Greek chi = 0.48). The dominance of the A-type AFM structure with the decrease of ΔJT can be ascribed to the change in the eg orbital state from d3z2-cursive Greek chi2 to dcursive Greek chi2-y2.
ASJC Scopus subject areas
- Physics and Astronomy(all)