Pressure-induced structural transformations, orbital order and antiferromagnetism in La0.75Ca0.25MnO3

被引：14

作者：

Kozlenko, D. P. ^{[1
]}

Dang, N. T. ^{[1
,2
]}

Kichanov, S. E. ^{[1
]}

Lukin, E. V. ^{[1
]}

Knizek, K. ^{[3
]}

Jirak, Z. ^{[3
]}

Dubrovinsky, L. S. ^{[4
]}

Voronin, V. I. ^{[5
]}

Savenko, B. N. ^{[1
]}

机构：

[1] JINR, Frank Lab Neutron Phys, Dubna 141980, Russia

[2] Tula State Univ, Dept Nat Sci, Tula 300600, Russia

[3] Acad Sci Czech Republ, Inst Phys, Prague 16253, Czech Republic

[4] Univ Bayreuth, Bayer Geoinst, D-95440 Bayreuth, Germany

[5] RAS, Ural Div, Inst Met Phys, Ekaterinburg 620219, Russia

来源：

EUROPEAN PHYSICAL JOURNAL B | 2013年 / 86卷 / 08期

关键词：

DENSITY-FUNCTIONAL THEORY; NEUTRON-DIFFRACTION; PHASE-DIAGRAM; TEMPERATURE; DEPENDENCE; TRANSITION; STATE;

D O I：

10.1140/epjb/e2013-40438-y

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

High pressure evolution of structural, vibrational and magnetic properties of La0.75Ca0.25MnO3 was studied by means of X-ray diffraction and Raman spectroscopy up to 39 GPa, and neutron diffraction up to 7.5 GPa. The stability of different magnetic ground states, orbital configurations and structural modifications were investigated by LDA + U electronic structure calculations. A change of octahedral tilts corresponding to the transformation of orthorhombic crystal structure from the Pnma symmetry to the Imma one occurs above P similar to 6 GPa. At the same time, the evolution of the orthorhombic lattice distortion evidences an appearance of the e(g) d(x2-z2) orbital polarization at high pressures. The magnetic order in La0.75Ca0.25MnO3 undergoes a continuous transition from the ferromagnetic 3D metallic (FM) ground state to the A-type antiferromagnetic (AFM) state of assumedly 2D pseudo-metallic character under pressure, that starts at about 1 GPa and extends possibly to 20-30 GPa.

引用

页数：8

共 43 条

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