Ultra-short pulsed Tm-doped fiber laser systems

The overall goal of the project is the development of novel powerful mid-IR ultrashort pulse fiber sources and also Watt-level mid-IR supercontinuum systems. The project objectives were (1) development of a reliable ultra-short pulsed 1.8-2.2 µm master oscillator in all-fiber format with fiber dispersion management; (2) development of the powerful up to 10 W fiber amplifier for ultra-short pulse amplification around 2 µm spectral range; (3) design and demonstration of a fiber based supercontinuum sou rce covering spectrum from the near infrared to the middle infrared, with average output powers up to 3W and spectral density up to 1mW/nm; (4) research and development of compact and robust all-fibre format power scalable sub-picosecond mid-IR sources for remote sensing, LIDAR, medical and scientific applications. As a result of the project we have achieved and even surpassed all the objectives set in the original proposal. The realized supercontinuum laser source has a spectral bandwidth close to octave and can be of an immediate interest for self-referenced frequency combs, trace gas sensing and environmental monitoring. We have also developed high power compact and robust tunable femtosecond laser systems and demonstrated a number of new applications, including fine material processing and oil and gas sensing, which open the way towards commercialization of these light sources. Based on the results of the project, we founded an NTNU spin-off company ATLA Lasers AS aimed at manufacturing of these lasers. The project results are at the stage of getting a patent protection by NTNU Technology Transfer Office. A patent application was filed out and submitted to the UK and US patents bureaus and a worldwide PCT application has been filed. Summarizing, the project resulted in the advanced laser device - laboratory demonstrator - which is ready to be further developed into commercial prototype. The work on industrial prototyping in close cooperation with the Norwegian industry, such as ESKO Kongsberg and STATOIL, is going on. This will lead to the conversion of the scientific results into real-world products.

The last several years have witnessed remarkable progress in high power fibre system technology as well as important break through in developing of optical saturable absorber materials in mid-IR for the intracavity passive modulation. Fiber pulsed systems based on master oscillator and fiber amplifier scheme with up to 3W average output power around 2 ?m spectral range have been demonstrated. Picoseconds and sub-picosecond scale pulses have also been obtained with use of SESAMs and carbon nanotube based a bsorbers. Mir-IR supercontinuum generation to 4.5 microns has been shown in fibers by pulsed laser pumping. Following these achievements, and based on feasibility studies we undertook in the field, we are putting forward a research project with firm commi tments targeted at the development of novel powerful mid-IR ultrashort pulse fibre sources and also Watt-level mid-IR supercontinuum fiber sources. The project's objectives are (1) development of a reliable ultra-short pulsed 1.8-2.2 µm master oscillator in all-fiber format with fiber dispersion management; (2) development of the powerful up to 10 W fiber amplifier for ultra-short pulse amplification around 2 microns mid-infrared spectral range; (3) design and demonstration of fiber based supercontinuum s ource covering spectrum from the near infrared to middle infrared, with average output powers up to 3W and spectral density up to 1mW/nm; (4) research and development of compact and robust all-fibre format power scalable sub-picosecond mid-IR sources for remote sensing, LIDAR,medical and scientific applications.