Abstract
A study is performed of the crystalline structure, magnetization, and magnetotransport properties of the system La2/3Ba1/3(Mn1−x Cox)O3 with perovskite structure. It is shown that cubic solid solutions exist over the entire range of cobalt concentrations 0⩽x⩽1. Compositions with x⩽0.2 are ferromagnets with maximum resistance near T C . Compositions with 0.2<x<0.4 manifest properties of inhomogeneous ferromagnets. Measurements of magnetic properties indicate the absence of long-range magnetic order in compositions with 0.5⩽x⩽0.9, which are probably spin glasses. The spontaneous magnetization of cobaltate (2μ B per formula unit) corresponds to ferromagnetic ordering of the moments of the Co3+ and Co4+ ions found in the intermediate spin state. It is conjectured that the magnetoresistance consists of an extrinsic and an intrinsic contribution. The first arises as a result of intergrain transport of spin-polarized charge carriers, and the second, as a result of magnetic ordering near T C . The magnetoresistance is essentially independent of the spontaneous magnetization and decreases abruptly as the cobalt concentration is increased with a corresponding transition from long-range to short-range magnetic order.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
A. J. Millis, P. B. Littlewood, and B. Shraiman, Phys. Rev. Lett. 74, 5144 (1995)
W. E. Pickett and D. J. Singh, Phys. Rev. B 55, R8642 (1997)
P. Majumdar and P. B. Littlewood, Nature (London) 395, 479 (1998)
D. I. Golosov, M. R. Norman, and K. Levin, Phys. Rev. B 58, 8617 (1998)
É. L. Nagaev, Usp. Fiz. Nauk 166, 833 (1996)
É. L. Nagaev, Usp. Fiz. Nauk 168, 917 (1998)
K. I. Kobayashi, T. Kimura, H. Sawada, K. Terakura, and Y. Tokura, Nature (London) 395, 677 (1998)
I. O. Troyanchuk, L. S. Lobanovsky, N. V. Kasper, M. Hervieu, A. Maignan, C. Michel, and H. Szymczak, Phys. Rev. B 58, 14903 (1998)
H. Kuwahara, Y. Tomioka, A. Asamitsu, Y. Moritomo, and Y. Tokura, Science 270, 961 (1995)
I. O. Troyanchuk, N. V. Kasper, D. D. Khalyavin, H. Szymczak, R. Szymczak, and M. Baran, Phys. Rev. Lett. 80, 3380 (1998)
G. Briceno, H. Chang, X. Sun, P. G. Schultz, and X. D. Xiang, Science 270, 273 (1995)
R. Mahendiran, A. K. Raychamdhuri, A. Chainani, and D. D. Sharma, J. Phys.: Condens. Matter 7, L561 (1995)
I. O. Troyanchuk, N. V. Kasper, D. D. Khalyavin, and E. F. Shapovalova, Phys. Rev. B 58, 2422 (1998)
N. Nishimori, K. Asai, and M. Mizoguchi, J. Phys. Soc. Jpn. 64, 1326 (1995)
I. O. Troyanchuk, N. V. Samsonenko, N. V. Kasper, and H. Szymczak, J. Phys.: Condens. Matter 9, 8287 (1997)
O. Toubemonde, F. Studer, A. Barnabe, A. Maignan, C. Martin, and B. Raveau, Eur. Phys. J. B 4, 159 (1998)
M. A. Senaris-Rodriguez and J. B. Goodenough, J. Solid State Chem. 118, 323 (1995)
W. Archibald, J. S. Zhou, and J. B. Goodenough, Phys. Rev. B 53, 14445 (1996)
Y. Qi, D. Y. Xing, and J. Dong, Phys. Rev. B 58, 2783 (1998)
Author information
Authors and Affiliations
Additional information
Zh. Éksp. Teor. Fiz. 116, 604–610 (August 1999)
Rights and permissions
About this article
Cite this article
Troyanchuk, I.O., Lobanovskii, L.S., Khalyavin, D.D. et al. Phase transitions and magnetic-transport phenomena in the system La2/3Ba1/3(Mn1−x Cox)O3 . J. Exp. Theor. Phys. 89, 321–324 (1999). https://doi.org/10.1134/1.558986
Received:
Issue Date:
DOI: https://doi.org/10.1134/1.558986