Ultrafast carrier dynamics in purified and as-grown single-walled carbon nanotube films

• 来源期刊: 中国物理（英文版）
• 关键词: carbon nanotubes carrier dynamics π-plasmon resonance charge transfer
• 年，卷（期）: 2005,（10）
• 页码范围: 2137-2140
• 页数: 4页
• 语种: 英文

摘要

Ultrafast time-resolved optical transmissions in purified and as-grown single-walled carbon nanotube films are measured at a temperature of 200K. The signal of the purified sample shows a crossover from photobleaching to photoabsorption. The former and the latter are interpreted as the state filling and the red shift of the π-plasmon,respectively. The signal of the as-grown sample can be perfectly fitted by a single-exponential with a time constant of 232fs. The disappearance of the negative component in the as-grown sample is attributed to the charge transfer between the semiconducting nanotubes and the impurities.