Unidirectional diagonal order and three-dimensional stacking of charge stripes in orthorhombic Pr{sub 1.67}Sr{sub 0.33}NiO{sub 4} and Nd{sub 1.67}Sr{sub 0.33}NiO{sub 4}

Journal Article · Tue Aug 15 04:00:00 EDT 2006 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.74.085112· OSTI ID:20853556

Huecker, M; Hill, J P; Tranquada, J M ^[1]; Zimmermann, M v ^[2]; Klingeler, R; Kiele, S; Geck, J; Buechner, B ^[3]; Bakehe, S N ^[4]; Zhang, J Z ^[1]; Revcolevschi, A ^[5]; Buttrey, D J ^[6]

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1. Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
2. Hamburger Synchrotronstrahlungslabor HASYLAB at Deutsches Elektronen-Synchrotron, 22603 Hamburg (Germany)
3. Leibniz-Institute for Solid State and Materials Research IFW Dresden, 01171 Dresden (Germany)
4. II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln (Germany)
5. Laboratoire de Physico-Chimie de l'Etat Solide, Universite Paris-Sud, 91405 Orsay Cedex (France)
6. Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716 (United States)

The interplay between crystal symmetry and charge stripe order in Pr{sub 1.67}Sr{sub 0.33}NiO{sub 4} and Nd{sub 1.67}Sr{sub 0.33}NiO{sub 4} has been studied by means of single crystal x-ray diffraction. In contrast to tetragonal La{sub 1.67}Sr{sub 0.33}NiO{sub 4}, these crystals are orthorhombic. The corresponding distortion of the NiO{sub 2} planes is found to dictate the direction of the charge stripes, similar to the case of diagonal spin stripes in the insulating phase of La{sub 2-x}Sr{sub x}CuO{sub 4}. In particular, diagonal stripes seem to always run along the short a axis, which is the direction of the octahedral tilt axis. In contrast, no influence of the crystal symmetry on the charge stripe ordering temperature itself was observed, with T{sub CO}{approx}240 K for La, Pr, and Nd. The coupling between lattice and stripe degrees of freedom allows one to produce macroscopic samples with unidirectional stripe order. In samples with stoichiometric oxygen content and a hole concentration of exactly 1/3, charge stripes exhibit a staggered stacking order with a period of three NiO{sub 2} layers, previously only observed with electron microscopy in domains of mesoscopic dimensions. Remarkably, this stacking order starts to melt about 40 K below T{sub CO}. The melting process can be described by mixing the ground state, which has a three-layer stacking period, with an increasing volume fraction with a two-layer stacking period.

• OSTI ID: 20853556
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 8 Vol. 74; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CHARGE DENSITY
COUPLING
DEGREES OF FREEDOM
ELECTRON MICROSCOPY
GROUND STATES
HOLES
LAYERS
MELTING
MONOCRYSTALS
NICKEL OXIDES
ORTHORHOMBIC LATTICES
OXYGEN
PRASEODYMIUM COMPOUNDS
SPIN
STOICHIOMETRY
STRONTIUM COMPOUNDS
SYMMETRY
THREE-DIMENSIONAL CALCULATIONS
X-RAY DIFFRACTION