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Passively mode-locked 10 GHz femtosecond Ti:sapphire laser



A Bartels, Dirk Heinecke, Scott Diddams


We report a mode-locked Ti:sapphire femtosecond laser emitting pulses as short as 42 fs at 10 GHz repetition rate. When operated with a spectrally-integrated average power greater than 1 W, the associated femtosecond laser frequency comb (FLFC) contains approximately 500 modes, each with power exceeding 1 mW. Spectral broadening of the pulses in nonlinear microstructured fiber yields comb elements with individual powers greater than 1 nW over 200 nm of spectral bandwidth. The modes of the emitted comb are resolved and imaged with a simple grating spectrometer and digital camera. Combined with absorption spectroscopy of rubidium vapor, this approach permits identification of the mode index and measurement of the carrier envelope offset frequency of the comb.
Optics Letters


femtosecond laser, frequency comb, spectroscopy, 10 GHz oscillator


Bartels, A. , Heinecke, D. and Diddams, S. (2008), Passively mode-locked 10 GHz femtosecond Ti:sapphire laser, Optics Letters, [online], (Accessed July 23, 2024)


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Created August 14, 2008, Updated October 12, 2021