Martin Siegel

Passively mode-locked Yb:KLu(WO 4 ) 2 thin-disk oscillator operated in the positive and negative dispersion regime

We demonstrate a passively mode-locked femtosecond Yb:KLu(WO(4))(2) thin-disk laser oscillator. Chirped-pulse operation in the positive dispersion regime as well as solitary operation have been realized, and the laser performance of both configurations are compared. In the solitary mode-locking regime the output power exceeds 25 W in a diffraction-limited beam, and pulse durations as short as 440 fs at a 34.7 MHz repetition rate have been generated. For the first time we present a chirped-pulse operation of a thin-disk oscillator that yields a maximum average output power of 9.5 W with a Fourier limit of 450 fs.

Passively mode-locked and cavity-dumped Yb:KY(WO4)2 oscillator with positive dispersion

We demonstrate, what is to our knowledge the first passively mode-locked Ytterbium based solid state high energy laser oscillator operated in the positive dispersion regime. Compared to solitary mode-locking the pulse energy can be increased with even broader spectral bandwidth. With high speed cavity dumping the laser generates 2 µJ-pulses at a 1 MHz repetition rate. The chirped output pulses are compressible down to 420 fs.

Microjoule pulses from a passively mode-locked Yb:KY(WO 4 ) 2 thin-disk oscillator with cavity dumping

We demonstrate, for the first time to our knowledge, a passively mode-locked femtosecond thin-disk oscillator with cavity dumping. A beta-barium-borate-based pockels cell imposes cavity dumping at a repetition rate of 1 MHz. The laser generates pulse energies up to 3 microJ with a pulse duration of 680 fs in a diffraction-limited beam.

Scalar generalized nonlinear Schrödinger equation-quantified continuum generation in an all-normal dispersion photonic crystal fiber for broadband coherent optical sources

We quantitatively predict the observed continuum-like spectral broadening in a 90-mm weakly birefringent all-normal dispersion-flattened photonic crystal fiber pumped by 1041-nm 229-fs 76-MHz pulses from a solid-state Yb:KYW laser. The well-characterized continuum pulses span a bandwidth of up to 300 nm around the laser wavelength, allowing high spectral power density pulse shaping useful for various coherent control applications. We also identify the nonlinear polarization effect that limits the bandwidth of these continuum pulses, and therefore report the path toward a series of attractive alternative broadband coherent optical sources.

Few-cycle oscillator pulse train with constant carrier-envelope- phase and 65 as jitter

We report on an octave-spanning Ti:sapphire laser oscillator stabilized to carrier-envelope-offset frequency zero, generating a pulse train with constant field profile for every pulse. Stabilization is realized using an extended self-referenced locking scheme enabling to lock the carrier envelope-offset phase with less than 65 attosecond rms timing jitter. The stabilized system features a pulse repetition rate of 100 MHz with pulses as short as 4.5 fs and 220 mW average output power. With this laser system it was possible for the first time to demonstrate a spectral interference pattern of 1011 oscillator pulses in an out-of-loop f-to-2f-interferometer.

Microjoule pulse energy from a chirped-pulse Ti:sapphire oscillator with cavity dumping.

A number of applications ranging from micro-machining to non-linear frequency conversion and high harmonic generation (HHG) would significantly benefit from femtosecond laser sources with pulse energies in the µJ-regime with MHz repetition rate at pulse durations below 100 fs. To this end in recent years several different concepts have been developed [1–3].

Generation of 9-μJ 420-fs pulses by fiber-based amplification of a cavity-dumped Yb:KYW laser oscillator

We report on the fiber-based amplification of a cavity-dumped Yb:KYW laser oscillator. With this system, we were able to generate 420-fs pulses with pulse energies of 9 μJ at a 1-MHz repetition rate.

Theoretical and experimental limits of cavity-dumping in passively mode-locked thin-disk oscillators.

The dynamical properties of a mode-locked thin disk laser with cavity-dumping in the solitary regime are studied using numerical simulations along with experimental data. Limitations of this system as well as their origin are identified. The results of these investigations agree very well with recently published experimental results. Based on these findings design criteria for future systems are deducted and estimates of possible pulse energies are made.

Pulsing dynamics in Ytterbium based chirped-pulse oscillators

The properties of passively mode-locked laser oscillators based on Ytterbium doped gain media are studied theoretically along with experimental data. Based on the chirped-pulse approach limitations due to excessive non-linearities are avoided, opening up new routes for energy scaling of mode-locked solid-state oscillators. Predictions about potential future pulse energies are made and possible experimental problems are discussed.

Theoretical and experimental limits of cavity-dumping in passively mode-locked thin-disk oscillators

Dynamical properties of mode-locked thin-disk lasers with cavity-dumping are studied with numerical simulations and experimental data. Limitations are identified, design criteria for future systems are deducted, and estimates of possible pulse energies given.