Ultrafast dynamics of photoexcitations in conjugated polymers

• Published in: Synthetic metals Vol. 84; no. 1; pp. 889 - 890
• Main Authors: Hayes, G.R., Samuel, I.D.W., Phillips, R.T.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 1997; Amsterdam Elsevier Science; New York, NY
• Subjects: Applied sciences; Electrical, magnetic and optical properties; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; poly(phenylenevinylene) and derivatives; Properties and characterization; semiconducting films; Time-resolved fast spectroscopy; Time-resolved fast spectroscopy; semiconducting films; poly(phenylenevinylene) and derivatives; Phenylenevinylene polymer; Conjugated polymer; Time resolution; Chemical solution; Phenylene derivative polymer; Film; Optical properties; Photoluminescence; Phenylenevinylene derivative polymer; Experimental study; Luminescence spectrum
• ISSN: 0379-6779; 1879-3290
• DOI: 10.1016/S0379-6779(96)04197-5

Measurements are reported of the time-resolved photoluminescence (PL) from unoriented films of poly( p-phenylenevinylene) [PPV], poly[2-methoxy,5-(2′-ethyl-hexyloxy)- p-phenylenevinylene] [MEH-PPV] and a cyano-substituted derivative of PPV, CN-PPV. The PL features observed for PPV and MEH-PPV are consistent with the ultrafast formation and subsequent energy migration of intrachain excitons followed by their decay through radiative and non-radiative processes. The dynamics of the PL in CN-PPV is substantially altered compared to that of PPV and MEH-PPV films and also to that of CN-PPV in solution. A transient high energy feature is observed that is not seen in continuous-wave (CW) measurements and a long-lived low energy feature which corresponds to the CW PL. These results are consistent with the formation of inter-chain excitations in CN-PPV films.