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Recent developments in compact ultrafast lasers

Nature volume 424, pages 831–838 (2003)Cite this article

Abstract

Ultrafast lasers, which generate optical pulses in the picosecond and femtosecond range, have progressed over the past decade from complicated and specialized laboratory systems to compact, reliable instruments. Semiconductor lasers for optical pumping and fast optical saturable absorbers, based on either semiconductor devices or the optical nonlinear Kerr effect, have dramatically improved these lasers and opened up new frontiers for applications with extremely short temporal resolution (much smaller than 10 fs), extremely high peak optical intensities (greater than 10 TW/cm2) and extremely fast pulse repetition rates (greater than 100 GHz).

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Figure 1: Pulses from a passively modelocked Nd:glass laser with a dye saturable absorber inside the laser resonator.
Figure 2: Improvements in ultrashort pulse generation since the first demonstration of a laser in 1960.
Figure 3: Kerr lens modelocking is obtained through a Kerr lens at an intracavity focus in the gain medium or in another material, where the refractive index increases with intensity Δn=n2 I(r,t), where n2 is the nonlinear refractive index and I(r,t) the radial- and time-dependent intensity of a short-pulsed laser beam.
Figure 4

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Acknowledgements

I would like to acknowledge many important contributions from my graduate students, post-docs and collaborators. I would like to mention Rüdiger Paschotta, Günter Steinmeyer, Franz Kärtner, Markus Haiml who have been senior researchers and project leaders in my group at different times during the last 10 years and Kurt Weingarten, Gabriel Spühler and Lukas Krainer from GigaTera Inc. on the most recent work on high pulse repetition rate lasers. This work has been supported by ETH, the Swiss National Science Foundation (SNF) and the Swiss Technology and Innovation Foundation (KTI).

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    Ursula Keller

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Keller, U. Recent developments in compact ultrafast lasers. Nature 424, 831–838 (2003). https://doi.org/10.1038/nature01938

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