JMP  Vol.3 No.7 , July 2012
Variable Range Hopping in Hydrogenated Amorphous Silicon-Nickel Alloys
ABSTRACT
On the insulating side of the metal-insulator transition (MIT), the study of the effect of low Temperatures T on the electrical transport in amorphous silicon-nickel alloys a-Si1-yNiy:H exhibits that the electrical conductivity follows, at the beginning, the Efros-Shklovskii Variable Range Hopping regime (ES VRH) with T-1/2. This behaviour showed that long range electron-electron interaction reduces the Density Of State of carriers (DOS) at the Fermi level and creates the Coulomb gap (CG). For T higher than a critical value of temperature TC, we obtained the Mott Variable Range Hopping regime with T-1/4, indicating that the DOS becomes almost constant in the vicinity of the Fermi level. The critical temperature TC decreases with nickel content in the alloys.

Cite this paper
A. Narjis, A. El kaaouachi, A. Sybous, L. Limouny, S. Dlimi, A. Aboudihab, J. Hemine, R. Abdia and G. Biskupski, "Variable Range Hopping in Hydrogenated Amorphous Silicon-Nickel Alloys," Journal of Modern Physics, Vol. 3 No. 7, 2012, pp. 517-520. doi: 10.4236/jmp.2012.37070.
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