This title appears in the Scientific Report :
2015
Please use the identifier:
http://dx.doi.org/10.1002/pssr.201510290 in citations.
Charge correlations in cobaltates La 2- x Sr x CoO 4
Charge correlations in cobaltates La 2- x Sr x CoO 4
Nano-phase separation in La2–xSrx CoO4 (schematically). Red areas: undoped La2CoO4 islands, blue areas: checkerboard charge ordered regions; black, green and blue balls represent nonmagnetic Co3+ ions, magnetic Co2+ ions and oxygen ions, respectively; green arrows indicate Co2+ spins [1, 2].We repor...
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Personal Name(s): | Guo, H. |
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Schmidt, W. / Tjeng, L. H. / Komarek, A. C. (Corresponding author) | |
Contributing Institute: |
Streumethoden; JCNS-2 JCNS-ILL; JCNS-ILL JARA-FIT; JARA-FIT Streumethoden; PGI-4 |
Published in: | Physica status solidi / Rapid research letters, 9 (2015) 10, S. 580 - 582 |
Imprint: |
Weinheim
Wiley-VCH
2015
|
DOI: |
10.1002/pssr.201510290 |
Document Type: |
Journal Article |
Research Program: |
Jülich Centre for Neutron Research (JCNS) Materials and Processes for Energy and Transport Technologies Quantum Condensed Matter: Magnetism, Superconductivity Controlling Collective States Controlling Collective States |
Publikationsportal JuSER |
Nano-phase separation in La2–xSrx CoO4 (schematically). Red areas: undoped La2CoO4 islands, blue areas: checkerboard charge ordered regions; black, green and blue balls represent nonmagnetic Co3+ ions, magnetic Co2+ ions and oxygen ions, respectively; green arrows indicate Co2+ spins [1, 2].We report on an elastic neutron scattering study of the charge correlations in La2–xSrx CoO4 with x = 1/3, 0.4 and 0.5. We found that the checkerboard charge ordering correlations present in the x = 0.5 sample persist in the x = 0.4 and 1/3 materials. These checkerboard charge ordering correlations are robust and explain the occurrence of nano-phase separation in layered cobaltates for Sr-concentrations away from half-doping. The half-integer reflections then arise from the nanometer-sized hole-rich regions (blue areas in title figure) instead of the undoped ones (red areas in title figure). The appearance of nano-phase separation is an important ingredient for understanding the formation of hour-glass shaped magnetic excitation spectra in La2–xSrx CoO4. |