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Ted Hänsch and Marco Bellini performed one of the key experiments leading to the invention of the femtosecond frequency comb (and, later, to the Nobel prize) in Florence.
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In 1997, we demonstrated the coherence in the process of supercontinuum generation that was the starting point to conceive the possibility of generating ultra-broadband self-calibrating optical frequency combs.
![The experiment showing high-contrast white-light interference fringes](/wp-content/uploads/SC-coherence-1024x563.jpg)