Ultrafast conductivity in a low-band-gap polyphenylene and fullerene blend studied by terahertz spectroscopy
(2009) In Physical Review B (Condensed Matter and Materials Physics) 79(24).- Abstract
- Time-resolved terahertz spectroscopy and Monte Carlo simulations of charge-carrier motion are used to investigate photoinduced transient conductivity in a blend of a low-band-gap polyphenylene copolymer and fullerene derivative. The optical excitation pulse generates free holes delocalized on polymer chains. We show that these holes exhibit a very high initial mobility as their initial excess energy facilitates their transport over defects (potential barriers) on polymer chains. The conductivity then drops down rapidly within 1 ps, and we demonstrate that this decrease occurs essentially by two mechanisms. First, the carriers loose their excess energy and they thus become progressively localized between the on-chain potential barriers-this... (More)
- Time-resolved terahertz spectroscopy and Monte Carlo simulations of charge-carrier motion are used to investigate photoinduced transient conductivity in a blend of a low-band-gap polyphenylene copolymer and fullerene derivative. The optical excitation pulse generates free holes delocalized on polymer chains. We show that these holes exhibit a very high initial mobility as their initial excess energy facilitates their transport over defects (potential barriers) on polymer chains. The conductivity then drops down rapidly within 1 ps, and we demonstrate that this decrease occurs essentially by two mechanisms. First, the carriers loose their excess energy and they thus become progressively localized between the on-chain potential barriers-this results in a mobility decay with a rate of (180 fs)(-1). Second, carriers are trapped at defects (potential wells) with a capture rate of (860 fs)(-1). At longer time scales, populations of mobile and trapped holes reach a quasiequilibrium state and further conductivity decrease becomes very slow.</p>. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1462372
- author
- Nemec, Hynek LU ; Nienhuys, Han-Kwang ; Perzon, Erik ; Zhang, Fengling ; Inganas, Olle ; Kuzel, Petr and Sundström, Villy LU
- organization
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- polymer blends, photoconductivity, Monte Carlo methods, hole mobility, energy gap, fullerenes, terahertz wave spectra, time, resolved spectra
- in
- Physical Review B (Condensed Matter and Materials Physics)
- volume
- 79
- issue
- 24
- publisher
- American Physical Society
- external identifiers
-
- wos:000267699700102
- scopus:68949127448
- ISSN
- 1098-0121
- DOI
- 10.1103/PhysRevB.79.245326
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Chemical Physics (S) (011001060)
- id
- 245c6667-66e7-47b3-9795-5a4c5dc6fb25 (old id 1462372)
- date added to LUP
- 2016-04-01 14:40:26
- date last changed
- 2022-02-04 22:10:25
@article{245c6667-66e7-47b3-9795-5a4c5dc6fb25, abstract = {{Time-resolved terahertz spectroscopy and Monte Carlo simulations of charge-carrier motion are used to investigate photoinduced transient conductivity in a blend of a low-band-gap polyphenylene copolymer and fullerene derivative. The optical excitation pulse generates free holes delocalized on polymer chains. We show that these holes exhibit a very high initial mobility as their initial excess energy facilitates their transport over defects (potential barriers) on polymer chains. The conductivity then drops down rapidly within 1 ps, and we demonstrate that this decrease occurs essentially by two mechanisms. First, the carriers loose their excess energy and they thus become progressively localized between the on-chain potential barriers-this results in a mobility decay with a rate of (180 fs)(-1). Second, carriers are trapped at defects (potential wells) with a capture rate of (860 fs)(-1). At longer time scales, populations of mobile and trapped holes reach a quasiequilibrium state and further conductivity decrease becomes very slow.</p>.}}, author = {{Nemec, Hynek and Nienhuys, Han-Kwang and Perzon, Erik and Zhang, Fengling and Inganas, Olle and Kuzel, Petr and Sundström, Villy}}, issn = {{1098-0121}}, keywords = {{polymer blends; photoconductivity; Monte Carlo methods; hole mobility; energy gap; fullerenes; terahertz wave spectra; time; resolved spectra}}, language = {{eng}}, number = {{24}}, publisher = {{American Physical Society}}, series = {{Physical Review B (Condensed Matter and Materials Physics)}}, title = {{Ultrafast conductivity in a low-band-gap polyphenylene and fullerene blend studied by terahertz spectroscopy}}, url = {{http://dx.doi.org/10.1103/PhysRevB.79.245326}}, doi = {{10.1103/PhysRevB.79.245326}}, volume = {{79}}, year = {{2009}}, }