[OPTICAL REVIEW Vol. 17, No. 3 (2010) 290-293]
© 2010 The Japan Society of Applied Physics

Carbon-Nanotube-Based Saturable Absorbers for Near Infrared Solid State Lasers

Petr A. OBRAZTSOV1,2*, Anatoliy. A. SIROTKIN2, Elena D. OBRAZTSOVA2, Yuri P. SVIRKO1, and Sergey V. GARNOV2

1Department of Physics and Mathematics, University of Joensuu, Yliopistokatu 7, FI-80100 Joensuu, Finland
2A. M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, 119991 Moscow, Russia

(Received September 12, 2009; Accepted January 20, 2010)

We demonstrate the passive mode-locking of a diode-pumped Nd+3:YAG (central wavelength: 1.32 μm; pulse duration: 50 ps; output energy: up to 70 μJ) laser using a polymer film containing single-wall carbon nanotubes. The mode-locking regime is stable at a pump repetition rate of up to 1 kHz. We also investigate the temporal evolution of the light-induced absorption change of the polymer film containing carbon nanotubes in the spectral range of 1.3–1.5 μm by femtosecond time-resolved pump–probe measurements. The measurements reveal that light-induced transmission exhibits fast and slow components that last 280 fs and more than 10 ps, respectively. The third-order susceptibility of the polymer film containing single wall carbon nanotubes is as high as 10-11 esu.

Key words: carbon nanotubes, saturable absorber, mode-locking, pump–probe, diode-pumped lasers, polymer film

*E-mail address: petr.obraztsov@joensuu.fi