Me. Rodriguez et al., THERMAL AND ELECTRICAL CHARACTERIZATION OF (CDTE)(1-X)TE-X COMPOSITES- ELECTRON-PHONON SYSTEM, Materials letters, 36(1-4), 1998, pp. 95-101
Pressed discs of mixed powders of CdTe (semiconductor) and Te (semimet
al) with different mass concentrations were thermally and electrically
characterized. In this granular system: (CdTe)(1-x)Te-x, studied in t
he entire range 0 less than or equal to x less than or equal to 1, whe
re x is the fractional weight of Te, it has been found to exist a perc
olation critical point, x(c) = 15.05%, for the electrical resistivity
(rho), by showing an abrupt decreasing of six orders of magnitude (rho
similar to 10(8) to rho similar to 10(2) Omega cm). The fractional we
ight value of x(c) = 15.05% corresponds to a volumetric fraction of 15
.4%, according within the error scattering with the accepted theoretic
al value of 16.0%, for a volumetric fraction at the critical percolati
on in a three-dimensional system based in a mixture of conductive-insu
lator materials. The study of the theoretical properties of the compos
ite were reduced to the analysis of the thermal diffusivity (a), as th
is is a dynamical property responsible for the establishment of the th
ermal equilibrium in a given material. The experimental results show a
complex dependence of ct as a function of the parameter x, evidencing
a thermal transport influenced by an electron-phonon interaction. (C)
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