| Original Articles |
|
|
|
|
Ultrafast Optical Response from a Novel Tri-Branched Copolymer |
| LI Bo1,2;MI Jun1;MENG Fan-Shun3;TIAN He3;QIAN Shi-Xiong1 |
| 1Department of Physics, Fudan University, Shanghai 200433
2National Key Laboratory of Surface Science, Fudan University, Shanghai 200433
3Institute of Fine Chemicals, East China University of Science and Technology, Shanghai 200237 |
|
| Cite this article: |
|
LI Bo, MI Jun, MENG Fan-Shun et al 2004 Chin. Phys. Lett. 21 1730-1733 |
|
|
|
Abstract A novel tri-branched copolymer is synthesized to show strong two-photon absorption and intense two-photon absorption induced fluorescence emission under the excitation of the femtosecond laser pulses at wavelength of 800nm. The dynamics of the excited state was measured by the pump-probe technique. In a one-colour pump-probe experiment at 800nm, there was an ultrafast transient absorption, followed by other two relaxation processes. The two-photon absorption process could be one origin for this ultrafast photoabsorption signal, which was further proven by two-colour pump--probe experiments. The other two decaying processes in the transient absorption dynamics have lifetime of about 15ps and 129ps, which reflect the intraband vibrational relaxation and the decay of two-photon excited state, respectively.
|
| Keywords:
33.80.Rv
34.30.+h
82.35.Ej
|
|
|
Published: 01 September 2004
|
|
| PACS: |
33.80.Rv
|
(Multiphoton ionization and excitation to highly excited states (e.g., Rydberg states))
|
| |
34.30.+h
|
|
| |
82.53
|
|
| |
-k
|
|
| |
82.35.Ej
|
(Nonlinear optics with polymers)
|
|
|
|
|
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
