Terahertz study of hole transport in pentacene thin films

Terahertz electromodulation spectroscopy is a novel tool for studying charge carrier transport in polycrystalline thin films. The technique selectively probes the high-frequency response of mobile carriers and is insensitive to scattering at grain boundaries as well as to trapping processes. In thin films of pentacene we find a hole mobility of 21 cm2 /Vs, which exceeds the largest previously reported values obtained in poly crystalline pentacene. Additionally, the data provide an upper limit of the hole conductivity effective mass of mh ≈ 0.8 me.

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