Mapping of exciton–exciton annihilation in MEH-PPV by time-resolved spectroscopy: experiment and microscopic theory. Issue 47 (27th November 2017)

• Record Type: Journal Article
• Authors: Hader, Kilian; Consani, Cristina; Brixner, Tobias; Engel, Volker
• Is Part Of: Physical chemistry chemical physics. Volume 19:Issue 47(2017)
• Page Start: 31989
• Page End: 31996
• Publication Date: 2017-11-27
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c7cp05168a
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Transient absorption traces taken on samples of the polymer MEH-PPV are measured as a function of the laser intensity. Abstract : Transient absorption traces taken on samples of the polymer MEH-PPV are measured as a function of the laser intensity. In increasing the laser power, different decay dynamics of the signal are obtained. This suggests that effective exciton–exciton annihilation takes place. The signals are interpreted using a microscopic quantum mechanical model. The analysis points at an ultrafast excitonic decay via interchain and intrachain annihilation, where the latter process is roughly thirty times slower. Afterwards, diffusion-induced annihilation and relaxation become effective and thus determine the long-time behavior of the excited-state decay.