TITLE

Tailoring of light emission properties of functionalized oligothiophenes

AUTHOR(S)
Caldas, Marilia J.; Pettenati, Emanuele; Goldoni, Guido; Molinari, Elisa
PUB. DATE
October 2001
SOURCE
Applied Physics Letters;10/15/2001, Vol. 79 Issue 16, p2505
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We investigate theoretically the light emission properties of short oligothiophenes containing a thienyl-S,S-dioxide moiety, which have recently been shown to exhibit strong photoluminescence efficiency and tunability. We find that the dioxide substitution tends to increase the torsion angle between rings and strongly affects the states at the optical band edges, in a way depending on the position of the substituted ring. We have identified a low-energy transition which is optically active only when the dioxide unit is inserted between two thiophene rings, as a result of increased inter-ring torsional angle also in the excited state. With the dioxide unit in a terminal position, planarity is favored in the excited state, and the transition is optically inactive. For short oligomers, this can lead to nonradiative decay quenching the luminescence. © 2001 American Institute of Physics.
ACCESSION #
5319236

 

Related Articles

  • Photoluminescence study of crosslinked reactive mesogens for organic light emitting devices. Contoret, A. E. A.; Farrar, S. R.; Khan, S. M.; O’Neill, M.; Richards, G. J.; Aldred, M. P.; Kelly, S. M. // Journal of Applied Physics;2/1/2003, Vol. 93 Issue 3, p1465 

    We study the spectroscopic properties of luminescent liquid crystals which show a glassy nematic phase at room temperature and then form polymer networks by polymerization using ultraviolet light. The reactive mesogens possess fluorene-based aromatic cores with either diene or acrylate...

  • Optical linewidths of InGaN light emitting diodes and epilayers. O'Donnell, K.P.; Breitkopf, T. // Applied Physics Letters;4/7/1997, Vol. 70 Issue 14, p1843 

    Presents a comparative study on the optical linewidths of photo- and electroluminescence from high-quality InGaN epilayers and commercial single quantum well light emitting diode structures. Insensitivity of the optical linewidths to temperature; Contribution of three mechanisms to the...

  • Photoluminescence decay dynamics in an InGaN/AlGaN/GaN double-heterostructure.... Mohs, Georg; Fluegel, Brian // Applied Physics Letters;9/11/1995, Vol. 67 Issue 11, p1515 

    Analyzes the occurrence of photoluminescence (PL) in InGaN/AlGaN/GaN blue light-emitting-diodes. Variation of intensity and wavelength excitation for PL analysis; Impact of stimulated emissions on recombination processes; Analysis of changes in decay of PL depending on carrier densities.

  • Enhanced ultraviolet photoluminescence from SiO[sub 2]/Ge:SiO[sub 2]/SiO[sub 2] sandwiched structure. Shen, J. K.; Shen, J.K.; Wu, X. L.; Wu, X.L.; Yuan, R. K.; Yuan, R.K.; Tang, N.; Zou, J. P.; Zou, J.P.; Mei, Y. F.; Mei, Y.F.; Tan, C.; Bao, X. M.; Bao, X.M.; Siu, G. G.; Siu, G.G. // Applied Physics Letters;11/13/2000, Vol. 77 Issue 20 

    SiO[sub 2]/Ge:SiO[sub 2]/SiO[sub 2] sandwiched structure was fabricated for exploring efficient light emission. After annealed in N[sub 2] (O[sub 2]<1%), this structure shows three photoluminescence (PL) bands at 293, 395, and 780 nm. The intensity of the 395 nm band is largely enhanced in...

  • Strained Ga[sub x]In[sub 1-x]P multiple quantum wire light-emitting diodes: A luminescence.... Pearah, P.J.; Stellini, E.M.; Chen, A.C.; Moy, A.M.; Hsieh, K.C.; Cheng, K.Y. // Applied Physics Letters;2/15/1993, Vol. 62 Issue 7, p729 

    Describes the photoluminescence and electroluminescence of strained Ga[sub x]In[sub 1-x]P quantum wire light emitting diodes. Display of anisotropic polarization; Growth of the structure by an in situ epitaxial method; Dependence of emission intensity on incident excitation polarization.

  • Multicolor oligothiophene-based light-emitting diodes. Gigli, G.; Ingana¨s, O.; Anni, M.; De Vittorio, M.; Cingolani, R.; Barbarella, G.; Favaretto, L. // Applied Physics Letters;3/12/2001, Vol. 78 Issue 11, p1493 

    We demonstrate wide tunability, from green to near infrared, of the electroluminescence emission of substituted oligothiophene compounds. The compounds are characterized by high chemical stability, electron affinities up to 3.1 eV and photoluminescence efficiencies up to 70%. These...

  • Enhanced electroluminescence using polystyrene as a matrix. He, Gufeng; Li, Yongfang; Liu, Jie; Yang, Yang // Applied Physics Letters;6/3/2002, Vol. 80 Issue 22, p4247 

    Poly[2-methoxy-5-(2′thyl-hexyloxy)-l,4-phenylene vinylene] (MEH-PPV) blends with polystyrene (PS) were used as emitting layers in polymer light-emitting diodes. Studies of photoluminescence and electroluminescence (El) of the blends indicate that interchain interactions were tremendously...

  • Optical properties of ZnO/GaN heterostructure and its near-ultraviolet light-emitting diode. Qing-Xuan Yu, D. M.; Bo Xu; Qi-Hong Wu, D. M.; Yuan Liao; Guan-Zhong Wang, D. M.; Rong-Chuan Fang, D. M.; Hsin-Ying Lee; Ching-Ting Lee // Applied Physics Letters;12/8/2003, Vol. 83 Issue 23, p4713 

    We report on photoluminescence in a ZnO/GaN heterostructure, which showed a donor–acceptor pair emission band at 3.270 eV and the longitudinal optical phonon replicas at 12 K. In comparison with p-type GaN, the positions of the peaks are redshifted. This may be associated with the...

  • Efficient polymer light emitting diodes with metal fluoride/Al cathodes. Yang, Xiaohui; Mo, Yueqi; Yang, Wei; Yu, Gang; Cao, Yong // Applied Physics Letters;7/30/2001, Vol. 79 Issue 5 

    We reported efficient polymer light emitting diodes with alkali and alkaline earth metal fluoride Al cathodes. The quantum efficiencies of these devices are more than two orders of magnitude higher than those in devices without fluoride layer, comparable to the best data reported with similar...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics