IPG Photonics

About: IPG Photonics is a based out in . It is known for research contribution in the topics: Laser & Fiber laser. The organization has 903 authors who have published 1241 publications receiving 63339 citations.

Laser damage resistant anti-reflection microstructures for mid-infrared metal-ion doped ZnSe gain media

Abstract: Power scaling of mid-infrared laser systems based on chromium and iron doped zinc selenide (ZnSe) and zinc sulfide (ZnS) crystals is being advanced through the integration of surface relief anti-reflection microstructures (ARMs) etched directly in the facets of the laser gain media. In this study, a new ARMs texture fabrication process is demonstrated for polycrystalline ZnSe and ZnS material that results in a significant increase in pulsed laser damage resistance combined with an average reflection loss of less than 0.5% over the wavelength range of 1.9-3.0μm. The process was utilized to fabricate ARMs in chromium-doped zinc selenide (Cr 2+ :ZnSe) materials supplied by IPG Photonics and standardized pulsed laser induced damage threshold (LiDT) measurements at a wavelength of 2.09μm were made using the commercial testing services of Spica Technologies. It was found that the pulsed LiDT of ARMs etched in ZnSe and Cr 2+ :ZnSe can match or even exceed the level of a well-polished surface, a survivability that is many times higher than an equivalent performance broad-band thin-film AR coating. The results also indicate that the ARMs plasma etch process may find use as a post-polish damage mitigation technique similar to the chemical immersion used to double the damage resistance of fused silica optics. ARMs etched in Cr 2+ :ZnSe were also evaluated by IPG Photonics for survivability under continuous wave (CW) laser operation at a pump laser wavelength of 1.94μm. Catastrophic damage occurred between power levels of 400-500 kilowatt per square centimeter for both as polished and ARMs textured samples indicating no reduction in CW damage resistance attributable to surface effects.

Single-mode high power multimode fiber laser system

Abstract: A high power single mode fiber laser system is configured with an active fiber including coextending multimode core (MM) and cladding around the MM core. The MM core is doped with one or more ions selected from rare earth and transitional metals and has a bottleneck cross in accordance with one aspect of the disclosure. The bottleneck cross-section includes a relatively small uniformly dimensioned input end region, a frustoconical region and a relatively large uniformly dimensioned amplifying region. The refractive step index of the MM core is configured with a central dip shaped and dimensioned along the input region so as not to disturb a Gaussian field profile of fundamental mode, gradually transform the Gaussian field profile into the ring profile of the fundamental mode and support the latter along the amplifying region. In accordance with a further aspect, the core is further provided with an output transforming region with the dip which gradually shapes the ring field profile in the Gaussian field profile further distortlessly supported by the output end region. A variety of end and side pumping arrangements are employed with the structures configured in accordance with the first and second aspects.

Recent Advances in High-Power and High Energy Multicore Fiber Lasers*

Abstract: Since the observation in June 2000 of a high-brightness beam emitted from a 7-core Yb-doped phase-locked fiber laser array, much progress has been made to advance this laser technology by (1) increasing the number of the Yb-doped cores from 7 to 19, (2) establishing a power-scaling model for fabricating a multicore fiber laser containing 127 cores, that can potentially yield an output power greater than 10 KW, (3) developing a demountable side-pumping coupler to allow injection of the diode laser pump directly into the fiber along its length, (4) improving the beam quality with appropriate choice of the fiber parameters, and (5) enhancing the Q-switched laser energy utilizing multicore fiber laser arrays. This paper will present details on these developments.