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Making ultrafast cycles of light

Ultrafast Optics
The ability to generate coherent optical frequency combs has had a huge impact on precision metrology, imaging, and sensing applications. On closer inspection, the broadband “white light” generated through the interaction of femtosecond mode-locked laser pulses is composed of billions or trillions of precisely spaced wavelengths of light. Carlson et al. demonstrate an alternative to the mode-locked laser approach—the electro-optic modulation of a continuous-wave laser light source can also generate optical frequency combs (see the Perspective by Torres-Company). The electro-optic modulation techniques can operate at much higher repetition rates than mode-locked lasers, which means they could potentially yield even more precise measurements.

Science , this issue p. [1358][1]; see also p. [1316][2]

 [1]: /lookup/doi/10.1126/science.aat6451
 [2]: /lookup/volpage/361/1316?iss=6409