1 / 20

High power VBG Yb-fiber laser

High power VBG Yb-fiber laser. Slope eff. ~75 %. Δλ = 0.4 nm. M 2 ~5.5. Yb-fiber Core:  30 m, NA 0.056 D-shaped cladding :  400 m, NA 0.49 Fiber length : ~8 m (abs. ~2 dB/m at 975 nm) Launch efficiency : ~90 %. VBG 1.5mm 3mm 5mm

timothyrobert
Download Presentation

High power VBG Yb-fiber laser

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. High power VBG Yb-fiber laser Slope eff. ~75 % Δλ = 0.4 nm M2~5.5 • Yb-fiber Core: 30 m, NA 0.056 • D-shaped cladding :  400 m, NA 0.49 • Fiber length : ~8 m (abs. ~2 dB/m at 975 nm) • Launch efficiency : ~90 % VBG 1.5mm 3mm 5mm Δλ = 0.22 nm, λcentre = 1066.0 nm, R= 99 % AR coated surface normal polished ~2o to the grating vector P. Jelger, P. Wang, J. K. Sahu, F. Laurell, and W. A. Clarkson, Opt. Expr. 16, 9507 (2008)

  2. Transversally chirped VBG Yb laser • > 100 W output • > 78 % slope efficiency • Tunable from 1064-1073 nm • <0.5 % power fluctuation over tuning range • Narrowband signal < 50 pm • Temporal stability <0.2 % rms • M2 = 1.2 • Single-polarization >18 dB PER SBS threshold approx. 5 kW

  3. Tunable, high-power, 2 wavelength Yb laser Dual-line lasing 78 W wavelength separation 0.03 - 2 THz, Power fluctuation<1 %.

  4. Ultra-fast lasers Kerr-Lens ML Ti:sapphire laser D.E. Spence, P.K. Kean, and W. Sibbet Opt. Lett. 16, 42 (1991) M. Piché, Opt. Commun. 86, 156 (1991) Patent for the Aperture (Coherent)

  5. The Frequency Comb T  = phase offset between carrier wave and wave envelope fm = mfrep + foffset frep= 1/T foffset = ( /2) frep Therefore if  = 0  foffset= 0  fm = mfrep The idea has revolutionized the art of frequency measurements Theodor W. Hänsch e John L. Hall, Nobel Prize for Physics (2005)

  6.  10-3 – 10-5 up to 105 amplifier compressor  103 - 105 oscillator stretcher High Peak Intensities Lasers Chirped Pulse Amplification (CPA) D. Strickland and G. Mourou (1985) Ti:Al2O3 : 1-10 mJ; f = 1-10 kHz TTT [Terawatt Table Top] Lasers : 100 TW (5 J, 50 fs) Petawatt-class Lasers (1,5 PW, i.e. 580 J and 460 fs)

  7. Historical Evolution of Pulse Duration From Femtoseconds to Attoseconds 4 fs 80 as: E. Goulielmakis et. al., Science 320, 1614 (2008)

  8. Everything...

  9. In Science Laser cooling Na-atom molasses 6 laser beams with frequency slightly shorter than the transition frequency. Reduced the energy of a cloud of atoms to form an optical molasses. Temperatures down to micro-Kelvin. Nobel prize in 1997 for Chu, Cohen-Tannoudji and Phillips

  10. The world's largest and highest-energy laser the National Ignition Facility at Lawrence Livermore In the NIF experiments 192 giant laser beams are focused on a cm-sized target filled with hydrogen fuel. NIF's goal is to fuse the hydrogen atoms' nuclei and produce net energy gain (Eout = 100 Ein) The beams compress the target to 100 billion times the atmosphere to a temperature of 100 million °C

  11. Imaging and displays – large, small or 3D

  12. Conclusions Acknowledgments Friends and laser family References can be found on www.laserphysics.kth.se Solid-state lasers • efficient • Reliable • tailored fun And….

  13. That´s all folks!

  14. Hollow fiber dye and Q-dots sources Scematic layout Photograph of Rodamine 6G filled fiber Green pumped hollow fibre in wich dye is pumped

  15. Functional optical materials and structures • Chemically and photostructured glasses • Domain engineered ferroelectrics • Quantum dots • Silicone elastomers • Microstructured silicon

  16. Acknowledgments Laser physics group National and international colleagues www.laserfest.org

  17. Limitations related to thermal loading 2 mm FEM simulation 1 kW 3 mm 5 mm Absorption 0.2%/cm Δ λ ~ 0.5 nm Significant problem for lowgain lasers and high circulatingpowers Temperature distribution Width of VBG [mm] • Chirp reduces reflectivity! • VBG would transmit more power! Distance into VBG [mm]

  18. > 30 W Single Frequency CW VBG OPO P. Zeil, et al. Optics Express, 22, 29907-29913 (2014).

More Related