Stabilization of charge and orbital ordered states by antiferromagnetism in the A-site ordered YBaMn2O6

Autor:	Zhang, X. N., Choi, K. -Y., Lemmens, P., Nakajima, T., Ueda, Y.
Rok vydání:	2009
Předmět:	Condensed Matter - Strongly Correlated Electrons Condensed Matter - Materials Science
Druh dokumentu:	Working Paper
Popis:	We report on Raman scattering measurements of the A-site ordered YBaMn2O6 in the wide temperature range of 10-650K. Upon cooling almost all phonon modes show pronounced temperature dependencies of frequency, linewidth, and scattering intensity. This suggests that the octahedra tilting, Mn-O bond angles and lengths vary with temperature in a concerted way. The remarkable feature is that the high-temperature metallic and the charge and orbital ordered (CO-OO) states coexist down to T_N=195K. In the antiferromagnetic state zone-folded modes are induced by the CO-OO superstructure and the phonon modes undergo an anomalous softening and narrowing. Our results evidence that the CO-OO state is stabilized by the spin ordering for temperatures below T_N. Comment: 4 pages, 3 figures, added reference and corrections
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0909.4494 Zobrazit plný text záznamu View this record from Arxiv