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Related papers: Orbital Correlations in Doped Manganites

200 papers

The nature of orbital order-disorder transition has been studied in the La(1-x)Nd(x)MnO(3) (x = 0.0-1.0) series which covers the entire range between two end points - LaMnO(3) and NdMnO(3) - as well as in La(0.85)Nd(0.1)Sr(0.05)MnO(3) and…

Strongly Correlated Electrons · Physics 2009-11-10 Dipten Bhattacharya , P. Sujatha Devi , H. S. Maiti

It is proposed that the observation of orbital ordering in manganite materials should be possible at the L_II and L_III edges of manganese using X-ray resonant scattering. If performed, dipole selection rules would make the measurements…

Condensed Matter · Physics 2009-10-31 C. W. M. Castleton , M. Altarelli

We report the first direct resonant soft x-ray scattering observations of orbital ordering. We have studied the low temperature phase of La$_{0.5}$Sr$_{1.5}$MnO$_4$, a compound that displays charge and orbital ordering. Previous claims of…

Strongly Correlated Electrons · Physics 2009-11-10 S. B. Wilkins , P. D. Spencer , P. D. Hatton , S. P. Collins , M. D. Roper , D. Prabhakaran , A. T. Boothroyd

We study the effect of quenched disorder on the ordering of orbital and magnetic degrees of freedom in a two-dimensional, two-band double-exchange model for $e_g$ electrons coupled to Jahn-Teller distortions. Using a real-space Monte Carlo…

Strongly Correlated Electrons · Physics 2008-05-23 Sanjeev Kumar , Arno P. Kampf

We have investigated the low temperature phase of a Nd0.5Sr0.5MnO3 single crystal by x-ray resonant scattering at the Mn K-edge of the (3 0 0), (0 3 0) and (0 5/2 0) reflections. Strong resonances were observed for the s-s' channel in the…

Strongly Correlated Electrons · Physics 2009-11-10 Javier Herrero-Martin , Joaquin Garcia Ruiz , Gloria Subias , Javier Blasco , Maria Concepcion-Sanchez

We study theoretically the collective orbital excitation named orbital wave in the orbital ordered manganites.The dispersion relation of the orbital wave is affected by the static spin structure through the coupling between spin and orbital…

Strongly Correlated Electrons · Physics 2007-05-23 Sumio Ishihara , Sadamichi Maekawa

In this paper I give a short review of some properties of the colossal magnetoresistance manganites, connected with the orbital degrees of freedom. Ions Mn{3+}, present in most of these compounds, have double orbital degeneracy and are…

Strongly Correlated Electrons · Physics 2009-11-07 D. I. Khomskii

We use neutron scattering to demonstrate the presence of lattice polarons and their short-range correlations for several samples of La$_{1-x}$Ca$_x$MnO$_3$ in the Ca doping range $0.15\leq x\leq 0.3$. We establish the doping dependence of…

Strongly Correlated Electrons · Physics 2009-10-31 Pengcheng Dai , J. A. Fernandez-Baca , N. Wakabayashi , E. W. Plummer , Y. Tomioka , Y. Tokura

We derive a realistic microscopic model for doped colossal magnetoresistance manganites, which includes the dynamics of charge, spin, orbital and lattice degrees of freedom on a quantum mechanical level. The model respects the SU(2) spin…

Strongly Correlated Electrons · Physics 2007-05-23 Alexander Weisse , Holger Fehske

We investigate the interplay between spin and orbital correlations in monolayer and bilayer manganites using an effective spin-orbital t-J model which treats explicitly the e_g orbital degrees of freedom coupled to classical t_{2g} spins.…

Strongly Correlated Electrons · Physics 2007-05-23 M. Daghofer , A. M. Oles , D. R. Neuber , W. von der Linden

We study theoretically the phase diagram of the double-layered perovskite manganites taking into account the orbital degeneracy, the strong Coulombic repulsion, and the coupling with the lattice deformation. Observed spin structural changes…

Strongly Correlated Electrons · Physics 2009-10-31 Ryo Maezono , Naoto Nagaosa

The charge and orbital ordering in Pr_{0.5} Ca_{0.5} MnO_3 is studied for the first time by ^{17}O NMR. This local probe is sensitive to spin, charge and orbital correlations. Two transitions exist in this system: the charge and orbital…

Strongly Correlated Electrons · Physics 2009-11-07 A. Yakubovskii , A. Trokiner , S. Verkhovskii , A. Gerashenko , D. Khomskii

An explanation is given for the charge order, orbital order and insulating state observed in half-doped manganese oxides, such as Nd$_{1/2}$Sr$_{1/2}$MnO$_{3}$. The competition between the kinetic energy of the electrons and the magnetic…

Strongly Correlated Electrons · Physics 2009-10-31 Jeroen van den Brink , Giniyat Khaliullin , Daniel Khomskii

We present high resolution high energy and resonant x-ray diffraction results from La2-2xSr1+2xMn2O7 for x=0.55,0.575 and 0.60. These compounds show superlattice reflections at wavevectors of (h+-\delta,k+-\delta,l) and…

Strongly Correlated Electrons · Physics 2009-11-10 T. A. W. Beale , P. D. Spencer , P. D. Hatton , S. B. Wilkins , M. von Zimmermann , S. D. Brown , D. Prabhakaran , A. T. Boothroyd

We use neutron scattering to investigate the doping evolution of the magnetic correlations in the single-layer manganite $\rm Pr_{\it 1-x}Ca_{\it 1+x}MnO_4$, away from the $x=0.5$ composition where the CE-type commensurate antiferromagnetic…

Strongly Correlated Electrons · Physics 2009-10-14 F. Ye , Songxue Chi , J. A. Fernandez-Baca , A. Moreo , E. Dagotto , J. W. Lynn , R. Mathieu , Y. Kaneko , Y. Tokura , Pengcheng Dai

Coexistence of mutually influencing ferroelectric and magnetic ordering at low temperature in hexagonal phase of rare-earth manganites gives rise to interesting physical phenomena. Here, we report a detailed analysis of powder neutron…

Materials Science · Physics 2014-05-13 A. K. Singh , S. D. Kaushik , V. Siruguri , S. Patnaik

The magnetic correlations in the charge- and orbital-ordered manganite La(0.5)Sr(1.5)MnO(4) have been studied by elastic and inelastic neutron scattering techniques. Out of the well-defined CE-type magnetic structure with the corresponding…

Strongly Correlated Electrons · Physics 2009-11-13 D. Senff , O. Schumann , M. Benomar , M. Kriener , T. Lorenz , Y. Sidis , K. Habicht , P. Link , M. Braden

A system of strongly-interacting electron-lattice polarons can exhibit charge and orbital order at sufficiently high polaron concentrations. In this study, the structure of short-range polaron correlations in the layered colossal…

Analyzing the orbital structure and lattice distortions in the CE phase of half-doped manganites, we demonstrate that the usual approach directly relating the orbital occupation of Jahn-Teller ions to the displacements of neighboring…

Strongly Correlated Electrons · Physics 2011-06-06 A. O. Sboychakov , K. I. Kugel , A. L. Rakhmanov , D. I. Khomskii

We present diffraction data on a single-layered manganite La(0.42)Sr(1.58)MnO4 with hole doping (x>0.5). Overdoped La(0.42)Sr(1.58)MnO4 exhibits a complex ordering of charges, orbitals and spins. Single crystal neutron diffraction…

Strongly Correlated Electrons · Physics 2012-01-12 H. Ulbrich , D. Senff , P. Steffens , O. J. Schumann , Y. Sidis , P. Reutler , A. Revcolevschi , M. Braden