Abstract
A giant isotope effect, wherein the low-temperature metallic state is replaced by an insulator state, was recently observed when 18O was substituted for 16O in (La0.25Pr0.75)0.7Ca0.3MnO3 [N. A. Babushkina, L. M. Belova, O. Yu. Gorbenko et al., Nature (London) 391, 159 (1998)]. In the present work, the temperature evolution of the magnetic structure of two samples of this compound is studied by neutron diffraction. One sample contained a natural mixture of oxygen isotopes, 99.7% 16O, while the other was enriched to 75% with the isotope 18O. It is established that the samples are crystallographically identical at room temperature. As the temperature decreases, the sample with 16O undergoes successive antiferromagnetic (T AFM=5150 K) and ferromagnetic (T FM=110 K) transitions, which lead to the establishment of a noncollinear ferromagnetic structure, while a purely antiferromagnetic (T AFM=150 K) order arises in the sample with 18O. The temperature dependences of the intensities of the diffraction peaks associated with the charge ordering differ substantially in samples with 16O and 18O, and they correlate with the behavior of their electric resistance and magnetic structure.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
C. N. R. Rao, A. K. Cheetham, and R. Mahesh, Chem. Mater. 8, 2421 (1996).
A. P. Ramirez, J. Phys.: Condens. Matter 9, 8171 (1997).
D. Cox, P. G. Radaeli, M. Marezio, and S.-W. Cheong, Phys. Rev. B 57, 3305 (1998).
C. Zener, Phys. Rev. 82, 403 (1951).
J. B. Goodenough, Phys. Rev. 100, 564 (1955).
Z. Jirak, S. Krupicka, Z. Simsa et al., J. Magn. Magn. Mater. 53, 153 (1985).
S. Jin, M. McCormac, T. H. Tiefel et al., J. Appl. Phys. 76, 6929 (1994).
A. J. Millis, Nature (London) 392, 147 (1998).
G. M. Zhao, K. Conder, H. Keller, and K. A. Muller, Nature (London) 381, 676 (1996).
J. P. Frank, I. Isaac, W. Chen et al., Phys. Rev. B 58, 5189 (1998).
N. A. Babushkina, L. M. Belova, O. Yu. Gorbenko et al., Nature (London) 391, 159 (1998).
G. M. Zhao, H. Keller, J. Hofer et al., Solid State Commun. 104, 57 (1997).
A. M. Balagurov, V. Yu. Pomyakushin, V. L. Aksenov et al., JETP Lett. 67, 705 (1998).
C. Ritter, M. R. Ibarra, J. M. De Teresa et al., Phys. Rev. B 56, 8902 (1997).
I. G. Krogh Andersen, E. Krogh Andersen et al., J. Solid State Chem. 113, 320 (1994).
Z. Jirak, S. Vratislav, and J. Zajicek, Phys. Solid State 52, K39 (1979).
H. Yoshizawa, R. Kajimoto, H. Kawano et al., Phys. Rev. B 55, 2729 (1997).
P. G. Radaelli, D. E. Cox, M. Marezio, and S.-W. Cheong, Phys. Rev. B 55, 3015 (1997).
H. Yoshizawa, H. Kawano, Y. Tomioka, and Y. Tokura, Phys. Rev. B 52, R13145 (1995).
N. A. Babushkina, L. M. Belova, V. I. Ozhogin et al., J. Appl. Phys. 83, 7369 (1998).
Author information
Authors and Affiliations
Additional information
Pis’ma Zh. Éksp. Teor. Fiz. 69, No. 1, 46–51 (10 January 1999)
Rights and permissions
About this article
Cite this article
Balagurov, A.M., Pomyakushin, V.Y., Sheptyakov, D.V. et al. Changes in the magnetic structure of (La0.25Pr0.75)0.7Ca0.3MnO3 upon the isotopic substitution of 18O for 16O. Jetp Lett. 69, 50–56 (1999). https://doi.org/10.1134/1.567983
Received:
Issue Date:
DOI: https://doi.org/10.1134/1.567983