Neutron-diffraction study of stripe order in La{sub 2}NiO{sub 4+{delta}} with {delta}= (2) /(15)

Journal Article · Thu Jan 01 04:00:00 EST 1998 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.57.1066· OSTI ID:565913

Wochner, P; Tranquada, J M ^[1]; Buttrey, D J ^[2]; Sachan, V ^[3]

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1. Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
2. Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716 (United States)
3. Materials Science Program, University of Delaware, Newark, Delaware 19716 (United States)

We report a detailed neutron-scattering study of the ordering of spins and holes in oxygen-doped La{sub 2}NiO{sub 4.133}. The single-crystal sample exhibits the same oxygen-interstitial order but better defined charge-stripe order than that studied previously in crystals with {delta}=0.125. In particular, charge order is observed up to a temperature at least twice that of the magnetic transition, T{sub m}=110.5 K. On cooling through T{sub m}, the wave vector {epsilon}, equal to half the charge-stripe density within an NiO{sub 2} layer, jumps discontinuously from (1) /(3) to 0.2944. It continues to decrease with further cooling, showing several lock-in transitions on the way down to low temperature. To explain the observed lock-ins, a model is proposed in which each charge stripe is centered on either a row of Ni or a row of O ions. The model is shown to be consistent with the l dependence of the magnetic peak intensities and with the relative intensities of the higher-order magnetic satellites. Analysis of the latter also provides evidence that the magnetic domain walls (charge stripes) are relatively narrow. In combination with a recent study of magnetic-field-induced effects, we find that the charge stripes are all O centered at T{gt}T{sub m}, with a shift towards Ni centering at T{lt}T{sub m}. Inferences concerning the competing interactions responsible for the temperature dependence of {epsilon} and the localization of charge within the stripes are discussed. {copyright} {ital 1998} {ital The American Physical Society}

• OSTI ID: 565913
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 2 Vol. 57; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIFERROMAGNETIC MATERIALS
DOMAIN STRUCTURE
HOLES
INTERSTITIALS
LANTHANUM OXIDES
MORIN
NEUTRON DIFFRACTION
NICKEL OXIDES
SPIN
SPIN ORIENTATION
TEMPERATURE RANGE 0065-0273 K