Biexcitons in π-conjugated oligomers

Intensity-dependent femtosecond transient-absorption study

Victor I Klimov, D. W. McBranch, N. Barashkov, J. Ferraris

Research output: Contribution to journalArticle

72 Citations (Scopus)

Abstract

We report femtosecond transient-absorption (TA) studies of a five-ring oligomer of poly(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.

Original languageEnglish
Pages (from-to)7654-7662
Number of pages9
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume58
Issue number12
Publication statusPublished - Sep 15 1998

Fingerprint

oligomers
Oligomers
Excitons
excitons
Pumps
pumps
solid state
Stimulated emission
decay
stimulated emission
oscillator strengths
Charge transfer
Absorption spectra
fluence
charge transfer
absorption spectra
Molecules
rings
excitation
LDS 751

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Biexcitons in π-conjugated oligomers : Intensity-dependent femtosecond transient-absorption study. / Klimov, Victor I; McBranch, D. W.; Barashkov, N.; Ferraris, J.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 58, No. 12, 15.09.1998, p. 7654-7662.

Research output: Contribution to journalArticle

@article{9552e00d5ee14b65adf56b2ecc8b1b6c,
title = "Biexcitons in π-conjugated oligomers: Intensity-dependent femtosecond transient-absorption study",
abstract = "We report femtosecond transient-absorption (TA) studies of a five-ring oligomer of poly(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.",
author = "Klimov, {Victor I} and McBranch, {D. W.} and N. Barashkov and J. Ferraris",
year = "1998",
month = "9",
day = "15",
language = "English",
volume = "58",
pages = "7654--7662",
journal = "Physical Review B-Condensed Matter",
issn = "1098-0121",
publisher = "American Physical Society",
number = "12",

}

TY - JOUR

T1 - Biexcitons in π-conjugated oligomers

T2 - Intensity-dependent femtosecond transient-absorption study

AU - Klimov, Victor I

AU - McBranch, D. W.

AU - Barashkov, N.

AU - Ferraris, J.

PY - 1998/9/15

Y1 - 1998/9/15

N2 - We report femtosecond transient-absorption (TA) studies of a five-ring oligomer of poly(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.

AB - We report femtosecond transient-absorption (TA) studies of a five-ring oligomer of poly(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.

UR - http://www.scopus.com/inward/record.url?scp=0001313414&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001313414&partnerID=8YFLogxK

M3 - Article

VL - 58

SP - 7654

EP - 7662

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 12

ER -