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Magnetotransport and Magnetic Properties of La0.7MnO3−δ and Pr0.65Ba0.05Ca0.3MnO3−δ Superlattices

Published online by Cambridge University Press:  14 March 2011

Srinivas V. Pietambaram ,
D. Kumar ,
Rajiv K. Singh  and
C. B. Lee
Srinivas V. Pietambaram
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400, U.S.A.
D. Kumar
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400, U.S.A.
Rajiv K. Singh
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400, U.S.A.
C. B. Lee
Affiliation:
Department of Electrical Engineering, North Carolina A & T University, Greensboro, North Carolina 27411, U.S.A.
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Abstract

In an effort to achieve high magnetoresistance ratios at high temperature and low fields, we have fabricated superlattice structures consisting of La0.7MnO3−δ (LMO) and Pr0.65Ba0.05Ca0.3MnO3−δ (PBCMO) systems where La0.7MnO3−δ is believed to act as a ferromagnetic biasing source to Pr0.65Ba0.05Ca0.3MnO3−Δ. LMO and PBCMO individually transform to ferromagnetic states at 240 K and 60 K respectively. A series of samples, in which the thickness of La0.7MnO3−δ is fixed and that of Pr0.65Ba0.05Ca0.3MnO3−δ varied from 1 to 8 unit cells, have been grown in situ on (100) LaAlO3 substrates using a pulsed laser deposition technique. Microstructural characterization carried out on these films show the presence of characteristic intense satellite peaks indicating the chemical modulation of the superlattice structure. The insulator-to-metal transition and the MR ratio, defined as [R(0)-R(H)/R(H)], where R(0) and R(H) are resistances in zero and applied fields, is found to vary with the number of unit cells. The samples with 1, 2, 5 and 8 unit cells of Pr0.65Ba0.05Ca0.3MnO3−δ show a transition temperature of 240 K, 230 K, 150 K and 160 K and MR ratio of 540%, 592%, 3150% and 2875 % respectively. We have observed an enhancement of magnetoresistance ratio in case of superlattices with thickness of PBCMO greater than 5 unit cells. We attribute this enhancement to a ferromagnetic biasing provided by the LMO layers acting as a ferromagnetic film below its transition temperature.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 614: Symposium F – Magnetic Materials, Structures & Processing for Information… , 2000 , F8.12.1
Copyright
Copyright © Materials Research Society 2000

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References

REFERENCES

1. Jin, S., Tiefel, T. H., McCormack, M., Fastnatch, R.A., Ramesh, R., and Chen, L. H., Science 264, 413 (1994).10.1126/science.264.5157.413Google Scholar
2. Manoharan, S. S., Satyalakshmi, K. M., Hegde, M. S., Prasad, V., and Subramanyam, S. V., J. Appl. Phys. 76, 3923 (1994).10.1063/1.357404Google Scholar
3. Ju, H. L., Kwon, C., Li, Qi, Greene, R. L., and Venkatesan, T., Appl. Phys. Lett. 65, 2108 (1994).10.1063/1.112808Google Scholar
4. Hundley, M. F., Hawley, M., Helfner, R. H., Jai, Q. X., Neumeir, J. J., Tesmer, J., Thomson, J. D., and Wu, X. D., Appl. Phys. Lett. 67, 860 (1995).10.1063/1.115529Google Scholar
5. Zeng, X. T. and Wong, H. K., Appl. Phys. Lett. 66, 3371 (1995).10.1063/1.113761Google Scholar
6. Mahendiran, R., Tiwary, S. K., Raychauduri, A. K., Ramakrishnan, T. V., Mahesh, R., Rangavittal, N., and Rao, C. N. R., Phys. Rev. B 53, 3348 (1996).10.1103/PhysRevB.53.3348Google Scholar
7. Zener, C., Phys. Rev. 82, 403 (1951).10.1103/PhysRev.82.403Google Scholar
8. Baibich, M. N., Broto, J. M., Fert, A., Dau, F. Nguyen van, Petroff, F., Eitenne, P., Creuzet, G., Friederich, A., and Chazelas, J., Phys. Rev. Lett. 61, 2472 (1988).10.1103/PhysRevLett.61.2472Google Scholar
9. Manoharan, S. Sundar, Satyalakshmi, K. M., Prasad, V., Subramanyam, S. V., and Hegde, M. S., Curr. Sci. 69, 356 (1995).Google Scholar
10. Gong, G. Q., Gupta, A., Xiao, G., Lecoeur, P., and McGuire, T. R., Phys. Rev. B 54, R3742 (1996).10.1103/PhysRevB.54.R3742Google Scholar
11. Kwon, C., Kim, K.-C., Robson, M. C., Gu, J. Y., Rajeswari, M., and Venkatesan, T., J. Appl. Phys. 81, 4950 (1997).10.1063/1.365008Google Scholar
12. Pietambaram, S. V., Kumar, D., Singh, R. K., Lee, C. B., and Vidya Kaushik, S., J. Appl. Phys. 86, 3317 (1999)10.1063/1.371208Google Scholar
13. Kumar, D., Pietambaram, S. V., Singh, R. K. and Lee, C. B., Proceedings of the 1998 MRS Spring Meeting, San Francisco, CA, USA Google Scholar
14. Gupta, A., Gong, G. Q., Xiao, Gang, Duncombe, P. R., Lecoeur, P., Trouilloud, P., Wang, Y. Y., Dravid, V. P., and Sun, J. Z., Phys. Rev. B 54, 15629 (1996).10.1103/PhysRevB.54.R15629Google Scholar