Gaussian distribution of traps

Here is the hole trap density, g is the degeneracy factor (taken as unity in the calculations), Etp is the ionization energy of the hole traps, Ev is the valence band edge (i.e. HOMO), Ny is the effective density of states for holes, at is the standard deviation of the Gaussian distribution of traps, and the factor expOS /F/fcr) arises due to the Poole-Frenkel effect. Analytical solution of (3.58) and (3.60) can not be obtained. Numerically computed results are shown in Fig. 3.29. 

In studies of low-mobility insulators, two types of continuous trap distributions are commonly used the exponential distribution of traps [364] and the Gaussian distribution of traps [365]. 

Fig. 8.28 Experimental values and a simulation out using a Gaussian distribution of traps with (solid lines) of the temperature-dependent j(V) a density A/t = 9 lo ...

In contrast to the symmetrical triphenylene derivatives, for many of the unsymmetrical derivatives, the mobility is noticeably field and/or temperature dependent. In such systems it is possible to fit the data to a model in which there is a Gaussian distribution of trap energies characterized by cr (Table 3.2). 

Recently the effect of intrinsic traps on hopping transport in random organic systems was studied both in simulation and experiment [72]. In the computation it has been assumed that the eneigy distribution of the traps features the same Gaussian profile as that of bulk states. 

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