Compensation of Incomplete Round Trip in an Herriott Multipass-Based Kerr-Lens Mode-Locked Ti:Sapphire Oscillator via an Output Coupler Position

• Published in: Japanese Journal of Applied Physics Vol. 50; no. 3; pp. 032705 - 032705-5
• Main Authors: Song, Dong Hoon, Hwang, Sung In, Ko, Do-Kyeong
• Format: Journal Article
• Language: English
• Published: The Japan Society of Applied Physics 01.03.2011
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.50.032705

We examined the soft-aperture Kerr-lens mode-locked femtosecond Ti:sapphire oscillator derived from an Herriott multi-pass cavity (HMPC). Additionally, a novel and simple configuration was provided to extend the cavity length, the HMPC consisting of notched, flat and curved ($R = 4$ m) mirrors by which beams were injected and extracted. To compensate for beams which failed to complete round trips, the configuration was designed and analyzed as a function of the output coupler position. Such an oscillator generated 21.5 nJ, 34 fs pulses at a repetition rate of approximately 13.5 MHz; the spectral bandwidth represented 20 nm, corresponding to a time-bandwidth product of 0.33, assuming a $\sech^{2}$ fit.