Crossover from the Mott Variable Range Hopping Conduction Regime to Nearest Neighbor Site Hopping Regime in ZnSxSe1-x Thin Films

Abstract

In this work, we study the behavior of resistivity as a function of temperature and for several samples of ZnSxSe1-x thin films with x = 0, 0.2, 0.4, 0.5, 0.6, 0.8 and 1.0 respectively. In fact, we re-analyze in our investigation experimental measurements obtained by M. Popa et al. [1] in the range of temperature from 300 K to 500 K. We showed that the resistivity follows a nearest neighbor site hopping conduction mechanism with 𝝆 = 𝝆𝟎𝐞𝐱𝐩 ( 𝑬𝒂 𝒌𝑩𝑻 ) for very high temperatures and Mott variable range hopping conduction with 𝝆 = 𝝆𝑪𝐞𝐱𝐩 (𝑻𝟎 𝑻 )𝟏/𝟒 for relatively low temperatures. The crossover between the two regimes can be explained by the competition between the localization length scale 𝝃𝒍𝒐𝒄and the hopping length scale 𝑹𝒉𝒐𝒑.