Percolative aspects in photoconductivity

Abstract

We present transient photocurrent measurements on samples containing a benztriazole derivative embedded in polycarbonate matrices and we obtain the effective carrier mobilities and their dependence on concentration. This dependence can be viewed in terms of a critical concentration ${p}_{c}$ and a critical exponent $\overline{t}$. Our values of ${p}_{c}=0.1$ and $\overline{t}=2.5$ are similar to recent findings on continuum percolation. In contrast to simple percolation, the mobility is also field and temperature dependent, obeying a Poole-Frenkel behavior.