Studies On High Power Widely Tunebale Optical Parametric Oscillator Pumped By Photonic Crystal Fiber Femtosecond Laser

Highly efficient generation of widely tunable and high average powerfemtosecond laser source from UV to mid-infrared is obtained based on nonlinearoptical parametric conversion technique, which is pumped by an Yb-dopedlarge-mode-area photonics crystal fiber laser. A pulse measurement device based onnonlinear technology is set up to characterize the phase and intensity of femtosecondpulses. This thesis mainly focuses on second-order nonlinear process and the mainapplication contains two parts: first, we present an experimental and a theoreticalanalysis of the femtosecond optical parametric oscillators(OPOs) based on MgOdoped periodically poled LiNbO3(MgO:PPLN), to achieve a widely-tunable,highpower, ultrafast femtosecond laser source; second, we report a device GRENOUILLE(grating-eliminated no-nonsense observation of ultrafast incident laser light E fields),which is the extremely simple version of second-harmonic generationfrequency-resolved optical gating, to measure the femtosecond pulses. The maincontents of this dissertation are listed as follows:1. We have simulated the dynamic process of OPOs and get the numerical modelfrom vibration noise to the self-consistent oscillator based on the three-waveinteraction equation and modeling of element in OPOs cavity.2. We have designed and constructed a femtosecond OPOs in a MgO-dopedperiodically poled LiNbO3pumped by an Yb3+-doped single-polarization doublecladding LMA(large-mode-area) PCFs (photonic-crystal-fibers). Femtosecond pulsesfrom UV to mid-infrared have been obtain by intracavity second-harmonic generation(SHG) and sum-frequency generation(SFG) in the OPO.3. Pulse self-compression in short pulse region (sub50fs) has been investigatedboth experimentally and theoretically. We reported a40.6fs signal pulse with865mW output power based on aYb: fiber laser pumped OPO with a5mm thickperiodically poled LiNbO3(PPLN). To our knowledge, this is the shortest pulse evergenerated based on fiber laser pumped or MgO: PPLN based OPO, and the highestpeak power ever generated from OPO.4. We have demonstrated a dielectric-mirror-free femtosecond optical parametricoscillator (OPO) using a4-prism-system instead of pump dichroic mirror. All mirrorsin the cavity are gold-coated mirror indicated that this type of OPO cavity is suitable for oscillating wavelength from1μm to20μm, make it economic and universal. Thetunable near infrared signal pulse and mid-infrared idler pulse is able to oscillate inthe new type cavity.5. We have demonstrated the extremely simple version of second-harmonicgeneration frequency-resolved optical gating, GRENOUILLE, to measure the phaseand intensity of ultrafast pulses. The dynamics of GRENOUILLE is analyzed in detailbased on the theory of second harmonics generation by the tight focusing Gaussianbeam in the frequency domain. The GRENOUILLE has been modeled and parametershave been optimized.