Variable Range Hopping in Hydrogenated Amorphous Silicon-Nickel Alloys


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.

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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.

Conflicts of Interest

The authors declare no conflicts of interest.


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