Time-resolved photoluminescence study of excitons in α-PTCDA as a function of temperature

摘要: ~Received 17 January 2003; revised manuscript received 19 May published 1 October 2003! In the present work, we analyze radiative and nonradiative recombination channels in a-PTCDA ~3,4,9,10-perylene tetracarboxylic dianhydride! by applying time-resolved photoluminescence ~PL! techniques 50 ns range between temperatures of T510 K T5300 K. The obtained PL spectra are decomposed into exponentially decaying components which can be assigned to different types excitons, including Frenkel three self-trapped two high-energy satellites. From temperature dependence spectra, gain some insight influence processes on decay time bands. At room temperature, from excitons oppositely charged ionic pairs is quenched due recombination. contrast this behavior, a band excimers shows only weak dependence, so that it becomes dominating mechanism at above T5200