title: Femtosecond VECSEL with tunable multi-gigahertz repetition rate.
abstract: We present a femtosecond vertical external cavity surface emitting laser (VECSEL) that is continuously tunable in repetition rate from 6.5 GHz up to 11.3 GHz. The use of a low-saturation fluence semiconductor saturable absorber mirror (SESAM) enables stable cw modelocking with a simple cavity design, for which the laser mode area on SESAM and VECSEL are similar and do not significantly change for a variation in cavity length. Without any realignment of the cavity for the full tuning range, the pulse duration remained nearly constant around 625 fs with less than 3.5% standard deviation. The center wavelength only changed ±0.2 nm around 963.8 nm, while the output power was 169 mW with less than 6% standard deviation. Such a tunable repetition rate is interesting for various metrology applications such as optical sampling by laser cavity tuning (OSCAT).
authors: Department of Physics, Institute for Quantum Electronics, Wolfgang-Pauli-Strasse 16, 8093 Zürich, Switzerland. siebero@phys.ethz.ch
authors: Oliver D
authors: OD
authors: Sieber
authors: Valentin J
authors: VJ
authors: Wittwer
authors: Mario
authors: M
authors: Mangold
authors: Martin
authors: M
authors: Hoffmann
authors: Matthias
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authors: Golling
authors: Thomas
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authors: Südmeyer
authors: Ursula
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