Felix Ruebel

Synchronously pumped femtosecond optical parametric oscillator with integrated sum frequency generation

A synchronously pumped femtosecond optical parametric oscillator (OPO) with intracavity sum frequency generation in a single, periodically poled MgO-doped LiNbO3 (MgO:PPLN) is reported. The used MgO:PPLN crystal contains in series two sections with different poling periods. The first section which generates the 2.5μm OPO idler wave is followed by a second section which generates the sum frequency of the pump and the idler radiation and thus provides at 589nm yellow 140fs long pulses with an average power of up to 190mW. This corresponds to an optical overall conversion efficiency of 15%.

Generation of Powerful Tunable Mid-Infrared Picosecond Laser Radiation Using Frequency Conversion in Periodically Poled Lithium Niobate

The generation of tunable mid-infrared picosecond laser radiation in the spectral range from 3-5µm by nonlinear frequency conversion in PPLN is reported. More than 3W output power at 3µm and 1W at 4.5µm were achieved.

5.7 W cw single-frequency laser at 671 nm by single-pass second harmonic generation of a 17.2 W injection-locked 1342 nm Nd : YVO 4 ring laser using periodically poled MgO : LiNbO 3

We demonstrate a continuous wave single-frequency laser at 671.1 nm based on a high-power 888 nm pumped Nd:YVO4 ring laser at 1342.2 nm. Unidirectional operation of the fundamental ring laser is achieved with the injection-locking technique. A Nd:YVO4 microchip laser serves as the injecting seed source, providing a tunable single-frequency power of up to 40 mW. The ring laser emits a single-frequency power of 17.2 W with a Gaussian beam profile and a beam propagation factor of M2<1.1. A 60-mm-long periodically poled MgO-doped LiNbO3 crystal is used to generate the second harmonic in a single-pass scheme. Up to 5.7 W at 671.1 nm with a Gaussian shaped beam profile and a beam propagation factor of M2<1.2 are obtained, which is approximately twice the power of previously reported lasers. This work opens possibilities in cold atoms experiments with lithium, allowing the use of larger ensembles in magneto-optical traps or higher diffraction orders in atomic beam interferometers.

Optimization of Cascaded Intracavity Sum Frequency Generation towards the Visible in Periodically Poled MgO-LiNbO 3

Optical parametric oscillation and simultaneous sum frequency generation towards the visible in the same MgO:PPLN crystal is investigated. The fs-radiation was systematically optimized in respect of output power and the temporal and spectral properties.

High efficient kHz repetition rate injection seeded picosecond optical parametric generator in LBO

We report on a high efficient kHz repetition rate ps OPG in LBO with total conversion efficiencies of ≫50% in the near infrared. Injection seeding reduced the spectral bandwidth from typically 40nm to 0.4nm.

MIR-generation with short and ultra short laser pulses using frequency conversion in periodically poled Lithium niobate

The generation of tunable mid-infrared (MIR) laser radiation in the spectral range from 4 μm to 5 μm by nonlinear frequency-conversion of laser pulses in periodically poled Lithium niobate (PPLN) is investigated. Results of several experiments including nanosecond-, picosecond- and femtosecond- laser systems are presented and the potential and limitations of PPLN as nonlinear material for the MIR frequency-conversion are discussed.

Generation of ultrashort pulses in the visible using cascaded intracavity processes in periodically poled MgO:LiNbO 3

We report on synchronously pumped OPOs with intracavity SHG or SFG in the same MgO:PPLN crystal. At e.g. 590 nm an output power of 190 mW was obtained with 140 fs pulses at a repetition rate of 81 MHz.

Synchronously Pumped Femtosecond Cascaded Optical Parametric Oscillation and Second Harmonic Generation in Periodically Poled MgO:SLN

We report on a synchronously pumped femtosecond cascaded OPO/SHG process in a single MgO:PPLN with an average output power of 160 mW at 583 nm pumped with 1.4 W at 780 nm.