Biexcitons in π-conjugated oligomers: Intensity-dependent femtosecond transient-absorption study
| العنوان: | Biexcitons in π-conjugated oligomers: Intensity-dependent femtosecond transient-absorption study |
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| المؤلفون: | Duncan W. McBranch, John P. Ferraris, N. N. Barashkov, Victor I. Klimov |
| المصدر: | Physical Review B. 58:7654-7662 |
| بيانات النشر: | American Physical Society (APS), 1998. |
| سنة النشر: | 1998 |
| مصطلحات موضوعية: | Nuclear magnetic resonance, Materials science, Absorption spectroscopy, Oscillator strength, Exciton, Ultrafast laser spectroscopy, Femtosecond, Stimulated emission, Molecular physics, Excitation, Biexciton |
| الوصف: | We report femtosecond transient-absorption (TA) studies of a five-ring oligomer of poly({ital para}-phenylene vinylene) prepared in two different forms: solid-state films and dilute solutions. At high pump fluences, in both types of samples, we observe generation of two-exciton states, which are detected by the evolution of TA spectra and dynamics with increasing pump intensity. In solutions, double excitation of molecules results in the formation of stable biexcitons with enhanced oscillator strength, leading to an increased efficiency of the radiative decay and a superlinear pump dependence of the stimulated emission. In solid-state samples, the two-exciton states are unstable and decay on the subpicosecond time scale due to ultrafast charge transfer, accompanied by generation of interchain excitons. {copyright} {ital 1998} {ital The American Physical Society} |
| تدمد: | 1095-3795 0163-1829 |
| DOI: | 10.1103/physrevb.58.7654 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::e0ddd79c1c0975a2f2130370f37590cb https://doi.org/10.1103/physrevb.58.7654 |
| Rights: | CLOSED |
| رقم الانضمام: | edsair.doi...........e0ddd79c1c0975a2f2130370f37590cb |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10953795 01631829 |
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| DOI: | 10.1103/physrevb.58.7654 |