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Determination of local high-frequency dielectric function during the cubic-to-tetragonal phase transformation in barium titanate

Published online by Cambridge University Press:  31 January 2011

Kalpana S. Katti
Affiliation:
Department of Materials Science and Engineering, University of Washington, Box 352120, Seattle, Washington 98195
Maoxu Qian
Affiliation:
Department of Materials Science and Engineering, University of Washington, Box 352120, Seattle, Washington 98195
Mehmet Sarikaya
Affiliation:
Department of Materials Science and Engineering, University of Washington, Box 352120, Seattle, Washington 98195
Masuru Miyayama
Affiliation:
Advanced Materials Department, Research Center for Advanced Science and Technology, University of Tokyo, Tokyo 153, Japan
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Abstract

Transmission electron energy loss spectroscopy was used to obtain local dielectric properties in barium titanate. The high frequency dielectric function of the material was studied dynamically during the cubic-to-tetragonal (ct) phase transformation in conjunction with the effect of a small amount (0.9%) of donor dopant (niobium). In order to obtain the local dielectric function during the phase transformation, Kramers–Kronig relations were applied to the energy loss measurements. The optical excitations in the energy loss spectra were consistent with band structure results from the literature. The Re (1/∈), real part of the inverse dielectric function, obtained from the energy loss data indicated a change at the phase transformation. Specifically, a broadening of the valence plasmon excitation is observed which is attributed to the order-disorder nature of the tc transformation. A 0.4 eV shift in the volume plasmon was observed in the Nb-doped sample in all regions (within grains as well as at grain boundaries), indicating a uniform incorporation of the dopant in the lattice. In this paper, the changes in the dielectric function, such as shifts in collective excitations, are attributed to a large contribution from loosely bound Nb electrons. Furthermore, it is demonstrated that it is possible to obtain local (≈10 nm) physical property of a complex material dynamically at relatively high temperature.

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Articles
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

1.Lines, M. E. and Glass, A. H., Principles and Applications of Ferroelectrics and Related Materials (Clarenden Press, Oxford, UK, 1977).Google Scholar
2.Jona, F. and Shirane, G., Ferroelectric Crystals (Dover Publication, New York, 1993).Google Scholar
3.Heywang, W. and Thomann, H., in Electronic Ceramics, edited by Steele, B. C. H. (Elsevier Applied Science, London and New York, 1991).Google Scholar
4.Heywang, W., J. Mater. Sci. 6, 1214 (1971).Google Scholar
5.Heywang, W., J. Am. Ceram. Soc. 47 (10), 484 (1964).CrossRefGoogle Scholar
6.Schwarz, R. N. and Wechsler, B. A., J. Am. Ceram. Soc. 73 (11), 3200 (1990).CrossRefGoogle Scholar
7.Schwartz, R. N., Wechsler, B. A., and West, L., Appl. Phys. Lett. 67, 1352 (1995).Google Scholar
8.Amin, A., J. Am. Ceram. Soc. 72 (3), 369 (1989).CrossRefGoogle Scholar
9.Ravel, B. and Stern, E. A., Physica B 208 & 209, 316 (1995).CrossRefGoogle Scholar
10.Ravel, B., Sicron, N., Yacoby, Y., Stern, E. A., Dogan, F., and Rehr, J. J., Ferroelectrics 164, 265 (1995).Google Scholar
11.Resolution in the Microscope, edited by Sarikaya, M., Special Issue of Ultramicroscopy 47, (13), 1 (1992).Google Scholar
12.Egerton, R. F., Electron Energy Loss Spectroscopy in the Electron Microscope, 2nd ed. (Plenum Press, New York, 1996).CrossRefGoogle Scholar
13.Daniels, J., Festenberg, C. V., Raether, H., and Zeppenfeld, K., in Springer Tracts in Modern Physics (Springer-Verlag, Berlin, 1970), Vol. 54, pp. 77135.Google Scholar
14.Hunt, J. A. and Williams, D. B., Ultramicroscopy 38, 47 (1991).Google Scholar
15.Browning, N. D., Yuan, J., and Brown, L. M., Ultramicroscopy 38, 291 (1991).CrossRefGoogle Scholar
16.Wang, Y. Y., Zhang, H., Dravid, V. P., Han, P. D., and Payne, D. A., Phys. Rev. B 48 (13), 9810 (1993).CrossRefGoogle Scholar
17.Y.Wang, Y., Ph.D. Dissertation (Virginia Polytechnic Institute and State University, 1990).Google Scholar
18.Dravid, V. P., Zhang, H., Wills, L. A., and Wessels, B. W., J. Mater. Res. 9 426 (1994).Google Scholar
19.Turowski, M. A. and Kelly, T. F., Ultramicroscopy 41, 41 (1992).CrossRefGoogle Scholar
20.Uspenskii, Y. A. and Rashkeev, S. N., Phys. Lett. A 153 (6–7), 373 (1991).Google Scholar
21.Hudson, L. T., Kurtz, R. L., Robey, S. W., Temple, D., and Stockbauer, R. L., Phys. Rev. B 47 (3), 1174 (1993).Google Scholar
22.Holma, M., Kitamura, M., and Chen, H., J. Appl. Phys. 76 (1), 451 (1994).Google Scholar
23.Nemeshkalenko, V. V. and Timoshevskii, A., Phys. Status Solidi B 127, 163 (1985).Google Scholar
24.Qian, M., Sarikaya, M., and Stern, E. A., Ultramicroscopy 59, 137 (1995).Google Scholar
25.Katti, K., Qian, M., and Sarikaya, M., in Structure and Properties of Interfaces in Ceramics, edited by Bonnell, D. A., Chowdhry, U., and Rühle, M. (Mater. Res. Soc. Symp. Proc. 357, Pittsburgh, PA, 1995), p. 121.Google Scholar
26.Arlt, G., J. Mater. Sci. 25, 2655 (1990).CrossRefGoogle Scholar
27.CRC Handbook of Chemistry and Physics (The Chemical Rubber Co., Cleveland, OH, 1967–68).Google Scholar
28.Magnetism and Magnetic Materials,” MRS Bull. XIII (6), 1641, June 1988) “Magnetism on a Microscopic Scale,” MRS Bull. XX (10), 30–63, Oct. (1995).Google Scholar
29.Semiconducting Nanocrystals,” MRS Bull. XX (8), 2339, Aug. (1995),Google Scholar
30.Crystal Engineering of High T c-Related Oxide Films,” MRS Bull. XIX, 2655, Sept. (1994).Google Scholar
31.Photorefractive Materials,” MRS Bull. XIX (3), 3255, March (1994).Google Scholar
32.Multilayered Materials,” MRS Bull. XV (2), 1944, Feb. (1990).Google Scholar