Publication detail

Raman antenna effect from exciton–phonon coupling in organic semiconducting nanobelts

WANG, M. GONG, Y. ALZINA, F. SVOBODA, O. BALLESTEROS, B. TORRES, C. XIAO, S. HE, J. ZHANG, Z.

Original Title

Raman antenna effect from exciton–phonon coupling in organic semiconducting nanobelts

Type

journal article in Web of Science

Language

English

Original Abstract

The highly anisotropic interactions in organic semiconductors together with the soft character of organic materials lead to strong coupling between nuclear vibrations and exciton dynamics, which potentially results in anomalous electrical, optical and optoelectrical properties. Here, we report on the Raman antenna effect from organic semiconducting nanobelts 6,13-dichloropentacene (DCP), resulting from the coupling of molecular excitons and intramolecular phonons. The highly ordered crystalline structure in DCP nanobelts enables the precise polarization-resolved spectroscopic measurement. The angle-dependent Raman spectroscopy under resonant excitation shows that all Raman modes from the skeletal vibrations of DCP molecule act like a nearly perfect dipole antenna IRaman ∝ cos4(θ − 90), with almost zero (maximum) Raman scattering parallel (perpendicular) to the nanobelt's long-axis. The Raman antenna effect in DCP nanobelt is originated from the coupling between molecular skeletal vibrations and intramolecular exciton and the confinement of intermolecular excitons. It dramatically enhances the Raman polarization ratio (ρ = I‖/I⊥ > 25) and amplifies the anisotropy of the angle-dependent Raman scattering (κRaman = Imax/Imin > 12) of DCP nanobelts. These findings have crucial implications for fundamental understanding on the exciton–phonon coupling and its effects on the optical properties of organic semiconductors.

Keywords

FIELD-EFFECT TRANSISTORS; CHARGE-TRANSPORT; SINGLE-CRYSTALS; SPECTROSCOPY; PENTACENE; 6,13-DICHLOROPENTACENE; FABRICATION; NANOWIRES; POLYMER; DEVICES

Authors

WANG, M.; GONG, Y.; ALZINA, F.; SVOBODA, O.; BALLESTEROS, B.; TORRES, C.; XIAO, S.; HE, J.; ZHANG, Z.

Released

27. 11. 2017

Publisher

ROYAL SOC CHEMISTRY

Location

THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND

ISBN

2040-3364

Periodical

NANOSCALE

Year of study

9

Number

48

State

United Kingdom of Great Britain and Northern Ireland

Pages from

19328

Pages to

19336

Pages count

9

URL

http://dx.doi.org/10.1039/C7NR07212K

BibTex

@article{BUT143260,
  author="Mao {Wang} and Yi {Gong} and Francesc {Alzina} and Ondřej {Svoboda} and Belén {Ballesteros} and Clivia Marfa Sotomayor {Torres} and Senbo {Xiao} and Jianying {He} and Zhiliang {Zhang}",
  title="Raman antenna effect from exciton–phonon coupling in organic semiconducting nanobelts",
  journal="NANOSCALE",
  year="2017",
  volume="9",
  number="48",
  pages="19328--19336",
  doi="10.1039/C7NR07212K",
  issn="2040-3364",
  url="http://dx.doi.org/10.1039/C7NR07212K"
}