We have examined a complete phase diagram of Y1-x Lu xMnO3 with 0≤x≤1 by using bulk measurements and neutron-diffraction studies. With increasing Lu concentration, Curie-Weiss temperature and Neel temperature are found to increase continuously while the two-dimensional nature of short-range magnetic correlation persists even in the paramagnetic phase throughout the entire doping range. At the same time, the lattice constants and the unit-cell volume get contracted with Lu doping, i.e., chemical pressure effect. This decrease in the lattice constants and the unit-cell volume then leads naturally to an increased magnetic exchange interaction as found in our local spin-density approximation band calculations. We also discover that there is strong correlation in the temperature dependence of a volume anomaly at TN and the magnetic moments.
J. Park and S. Lee and M. Kang and K. Jang and C. Lee and S. V. Streltsov and V. V. Mazurenko and M. V. Valentyuk and J. E. Medvedeva and T. Kamiyama and J. Park, "Doping Dependence of Spin-Lattice Coupling and Two-Dimensional Ordering in Multiferroic Hexagonal Y1-xLuxMnO3 (0 ≤ x ≤ 1)," Physical Review B - Condensed Matter and Materials Physics, vol. 82, no. 5, pp. 054428-1-054428-9, American Physical Society (APS), Aug 2010.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevB.82.054428
International Standard Serial Number (ISSN)
Article - Journal
© 2010 American Physical Society (APS), All rights reserved.