Carrier Generation Process on Photoconductive Polymer Films as Studied by Magnetic Field Effects on the Charge-Transfer Fluorescence and Photocurrent

• DOI: 10.1021/jp0453212
• Publication Date: 2005-05-05T04:54:49Z
• Authors: Fuyuki Ito; Tadaaki Ikoma; Kimio Akiyama; Akira Watanabe; Shozo Tero-Kubota
• Keywords: Photocurrent; Quantum yield; Photoconductivity; Thermalisation

We have studied the magnetic field effects (MFEs) on charge-transfer fluorescence and transient photocurrent of a 1,2,4,5-tetracyanobenzene-doped poly(N-vinylcarbazole) film, which reflect recombination escape yields carriers, respectively. The yield dependence external (B) clearly shows two types MFEs, growth with increasing B due to hyperfine mechanism (HFM) negative dip level-crossing (LCM). On other hand, indicates complementary MFEs sharp decrease in then positive dip. Simultaneous observation HFM- LCM-MFEs proves stepwise hole-hopping rather long-range hole-jumping one. quantitative analysis is performed using stochastic Liouville equations (SLE) for one-dimensional lattice model hole hops take place between nearest neighbor carbazole units spin conservation. SLE provides transfer rate constants 7.0 × 107 4.5 108 s-1, boundary site number ion pairs estimated by best fit experimental results. interionic distance pair including eight sites agrees thermalization Onsager model. Hence, it concluded that elementary processes applied molecular amorphous solids are than jump.