Abstract
Electrical resistivity and positron lifetime measurements have been carried out as a function of temperature and germanium concentration in the FeSi1− x Ge x system. The lattice constant is seen to increase with Ge concentration. Electrical resistivity measurements as a function of temperature in the 4 K to 300 K temperature range show a semiconducting behaviour for all x. The gap value Δ decreases with increase in x. These results are discussed in conjunction with band structure calcula¬tions. Positron lifetime measurements show that, in FeSi, at temperatures below 200 K there is an unusual decrease in the positron lifetime, τ. With the help of lifetime calculations, the observed decrease is inferred to arise due to the delocalisation of the Fe d electron, an electronic structure change consequent to the Kondo singlet formation.
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References
G. Aeppeli and Z. Fisk, Comments Condens. Matt. Phys., 16, 155 (1992).
V. Jaccarino et al, Phys. Rev., 160, 476 (1967).
T. Kasuya, Physica B, 223 & 224, 402 (1996).
Z. Fisk et. al, Physica B, 223 & 224, 409, (1996).
R. Julien and R. M. Martin, Phys. Rev B, 26, 6173 (1982).
J. D. Thompson, Physica B, 223 & 224, 643 (1996).
J. D. Thompson, Handbook on Physics and Chemistry of Rare Earths, 19, edited by K. A. Gschneidner, Jr., L. Eyring, G. H. Lander and G. R. Choppin, 383 (1994).
S. Yoshii et. al, Physica B, 223 & 224, 421 (1996).
P. Wachter, Handbook on Physics and Chemistry of Rare Earths, 19, edited by K. A. Gschneidner, Jr., L. Eyring, G. H. Lander and G. R. Choppin, 177 (1994).
D. T. Adroja et. al, Physica B 223 & 224, 275 (1996).
K. Friemelt et. al Annalen der Physik, 5, 175 (1996).
B. C. Sales et al, Phys. Rev. B, 50, 8207 (1994).
A. Bharathi et al, Physica B, submitted.
R.N. West, Adv. Phys., 22, 263 (1973).
R.M. Nieminen in, Positron Solid State Physics, edited by W. Brandt and A.Dupasquier (North-Holland, Amsterdam, 1983), p. 359.
A. Bharathi et. al, Phys. Rev. B, submitted.
S. Takagi et al J. Phys. Soc. Jpn 50, 2539 (1981).
O. K. Anderson, Phys. Rev. B, 12, 3060 (1975).
L. F. Matheiss and D. R. Hamann, Phys. Rev. B 47, 2219 (1993).
L. Fu et al, Phys. Rev B 49, 2219 (1994).
M.J. Puska and R.M. Nieminen, J. Phys. F 13, 333 (1983).
A. Bharathi et al, J. Phys. Cond. Matter. 1, 1467 (1988).
C. M. Varma, Phys. Rev. B 50, 9952 (1994).
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Bharathi, A., Hariharan, Y., Mani, A., Sundar, C.S. (1998). Electrical Resistivity and Positron Lifetime Studies in the Kondo Insulating System, FeSi1−xGex . In: Kumar, V., Sengupta, S., Raj, B. (eds) Frontiers in Materials Modelling and Design. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-80478-6_16
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DOI: https://doi.org/10.1007/978-3-642-80478-6_16
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