Ultrafast Lasers

Since they generate very short light-matter interaction times and large radiation intensities, lasers with ultrashort pulses (USP lasers) have great advantages for applications with special requirements. They enable high-precision material processing – even with difficult-to-process materials – with negligible heat input into the processed workpieces.

At Fraunhofer ILT, USP beam sources are being developed that provide application-specific optimized wavelengths, powers or pulse frequencies. In the area of power scaling of USP laser systems, Fraunhofer ILT has already achieved several record levels. Currently, it is focusing its research and development on laser amplifiers with wavelengths in the near infrared, pulse durations of 10 fs to 1 ps, output powers of 100 mW to 5 kW and pulse energies in the range 1 nJ to 100 mJ with diffraction-limited beam quality. The institute uses and continues to develop INNOSLAB, rod and disk laser amplifiers as well as sources for coherent VUV and EUV radiation. A promising future field of application for high-power ultrashort pulse lasers is the laser cutting and removal of difficult-to-machine materials, such as CFRP, with high speeds and high precision. For this purpose, technologies for pulse reduction will be developed further and a power scaling in the multi-kilowatt range targeted.

The services offered by Fraunhofer ILT include feasibility studies, simulations, experimental investigations, the automation of lasers, the development of industry-oriented prototypes, and consulting.

fs-Oscillators

• KLM
• Cr:Colquiriite
• Yb:YAG / KGW / Lu2O3
• Modeling Kerr-effect, pumping radiation, gain saturation

Broad Band Amplifier

• Diode pumped up to 1kW average output power
• Yb:YAG / KGW / Lu2O3
• Cr:Colquiriite
• 3D modeling of 3-level systems and beam propagation

Dispersion Measurement

• Group delay - dispersion measurement of optics
• Wavelength range l = 250 - 1700 nm
• Resolution Dl = 1 nm / DD2 = 3fs2

Generation of Radiation

• Incoherent X-rays
• Coherent EUV / XUV
• Electrons

Schulte, J., Sartorius, T., Weitenberg, J., Vernaleken, A., Russbueldt, P.:
Nonlinear pulse compression in a multi-pass cell
Opt. Lett. 41 (19), 4511-4514 (2016)

Esser, D., Staasmeyer, J.-H., Weitenberg, J., Rußbüldt, T., Sartorius, T., Hoffmann, H.-D.:
Fused-silica mirror substrates with laser-microstructured openings with reduced chipping
CLEO_Europe 2015. 21-25 June 2015 in Munich. CE_10_3. (2015)

Finger, J., Kalupka C., Reininghaus, M.:
High power ultra-short pulse laser ablation of IN718 using high repetition rates
J. Materials Processing Technol. 226 (Dec.), 221-227 (2015)

Fornaroli, C., Holtkamp, J., Gillner, A.:
Dicing of thin silicon wafers with ultra-short pulsed lasers in the range from 200 fs up to 10 ps
J. Laser Micro/Nanoeng. 10 (2), 229-233 (2015)

Russbueldt, P., Hoffmann, D., Höfer, M., Löhring, J., Luttmann, J., Meissner, A., Weitenberg, J., Traub, M., Sartorius, T., Esser, D., Wester, R., Loosen, P., Poprawe R.:
Innoslab amplifiers
IEEE Journal of Selected Topics in Quantum Electronics 21,
3100117-3100117 (2015)

Weitenberg, J., Rußbüldt, P.,  Pupeza, I., Udem, Th., Hoffmann, H.-D.,  Poprawe, R.:
Geometrical on-axis access to high-finesse resonators by quasi-imaging: a theoretical description
Journal of Optics A-Pure and Applied Optics 17, 1-17 (2015)

Bensmann, S., Gaußmann, F., Lewin, M., Wüppen, J., Nyga, S., Janzen, C., Jungbluth, B., Taubner, T.:
Near-field imaging and spectroscopy of locally strained GaN using an IR broadband laser
Opt. Expr. 22 (19), 22369-22381 (2014)

Carstens, H., Lilienfein, N., Holzberger, S.: Jocher, C., Eidam, T., Limpert, J., Tünnermann, A., Weitenberg, J., Malgamdi, A., Alahmed, Z., Azzeer, A., Apolonski, A., Fill, E., Pupeza, I., Krausz, F.:
Thermal limitations for power scaling of femtosecond enhancement cavities
High Intensity Lasers and High Field Phenomena (HILAS) 2014. Paper: HTu1C.6 (3 S.) (2014)

Carstens, H., Lilienfein, N., Holzberger, S., Jocher, C., Eidam, T., Limpert, J., Tünnermann, A., Weitenberg, J., Yost, D. C., Alghamdi, A., Alahmed, Z., Azzeer, A., Apolonski, A., Fill, E., Krausz, F., Pupeza, I.:
Megawatt-scale average-power ultrashort pulses in an enhancement cavity
Opt. Lett. 39 (9), 2595-2598 (2014)

Gronloh, B., Russbueldt, P., Jungbluth, B., Hoffmann, H.-D.:
Ultrafast green laser exceeding 400 W of average power
Proc. SPIE 9135, 91350C (11 S.)  (2014)

Carstens, H., Lilienfein, N., Holzberger, S.: Jocher, C., Eidam, T., Limpert, J., Tünnermann, A., Weitenberg, J., Malgamdi, A., Alahmed, Z., Azzeer, A., Apolonski, A., Fill, E., Pupeza, I., Krausz, F.:
Thermal limitations for power scaling of femtosecond enhancement cavities
High Intensity Lasers and High Field Phenomena (HILAS) 2014. Paper: HTu1C.6 (3 S.) (2014)

Carstens, H., Lilienfein, N., Holzberger, S., Jocher, C., Eidam, T., Limpert, J., Tünnermann, A., Weitenberg, J., Yost, D. C., Alghamdi, A., Alahmed, Z., Azzeer, A., Apolonski, A., Fill, E., Krausz, F., Pupeza, I.:
Megawatt-scale average-power ultrashort pulses in an enhancement cavity
Opt. Lett. 39 (9), 2595-2598 (2014)

Petraviciute-Lötscher, L., Schneider, W., Rußbüldt, P., Gronloh, B., Hoffmann, H.-D., Kling, M. F., Apolonski, A.:
Direct low-harmonic generation in gas at MHz repetition rate
Lasers and Electro-Optics Europe (CLEO EUROPE/IQEC)
Conference on and International Quantum Electronics Conference, Munich 12-16 May 2013 (1 S.) (2013)

Büsing, L., Bonhoff, T., Gottmann, J., Loosen, P.:
Deformation of ultra-short laser pulses by optical systems for laser scanners
Opt. Expr. 21 (21), 24475-24482 (2013)

Carstens, H., Holzberger, S., Kaster, J., Weitenberg, J., Pervak, V., Apolonski, A., Fill, E., Krausz, F., Pupeza, I.:
Large-mode enhancement cavities
Opt. Expr. 21 (9), 11606-11617 (2013)

Finger, J., Weinand, M., Wortmann, D.:
Ablation and cutting of carbon-fiber reinforced plastics using picosecond pulsed laser radiation with high average power
J. Laser Appl. 25, (4), 042007-1 (5 S.) (2013)

Pupeza, I., Holzberger, S., Eidam, T., Esser, D., Weitenberg, J.,
Rußbüldt, P., Rauschenberger, J., Limpert, J., Udem, Th., Tünnermann, A., Hänsch, T. W., Apolonski, A., Krausz, F., Fill, E.:
Compact high-repetition-rate source of coherent 100 eV radiation
Nature Photonics 7, (8) 608-612 (2013)

Tulea, C., Caron, J., Wahab, H., Gehlich, N., Hoefer, M., Esser, D., Jungbluth, B., Lenenbach, A., Noll, R.:
Highly efficient nonthermal ablation of bone under bulk water with a frequency-doubled Nd:YVO4 picosecond laser
Proc. SPIE 8565, 85656 E-1 (11 S.) (2013)

Zhuang, F., Jungbluth, B., Gronloh, B., Hoffmann, H.-D., Zhang, G.:
Dual-wavelength, continuous-wave Yb:YAG laser for high-resolution photothermal common-path interferometry
Appl. Opt. 52 (21), 5171-5177 (2013)

Gronloh, B., Russbueldt, P., Schneider, W., Jungbluth, B., Hoffmann, H.-D.:
High average power sub-picosecond pulse generation at 515 nm by extracavity frequency doubling of a mode-locked Innoslab MOPA
Proc. SPIE 8235, 10 S., (2012)

Reininghaus, M., Wortmann, D., Finger, J., Faley, O., Poprawe, R., Stampfer, C.:
Laser induced non-thermal deposition of ultrathin graphite
Appl. Phys. Lett. 100, Nr. 15, 1-3, (2012)

Wortmann, D., Koch, J., Reininghaus, M., Unger, C., Hulverscheidt, C., Ivanov, D., Chichkov, B. N.:
Experimental and theoretical investigation on fs-laser-induced nanostructure formation on thin gold films
J. Laser Appl. 24, 4 (Special ed). 6 S. (2012)

Wueppen, J., Nyga, S., Taubner, T., Jungbluth, B.:
Ultrafast mid-IR laser source with a tuning range from 9 to 16 microns based on nonlinear frequency conversion
In: mirsens2, International Workshop on Opportunities and Challenges
in Mid-Infrared Laser-Based Gas Sensing, October 18-20, 2012, Wroclaw
pp. 18-19 (2012)

Mans, T., Dolkemeyer, J., Russbüldt, P., Schnitzler, C.:
Highly flexible ultrafast laser system with 260W average power
Proc. SPIE 7912, 79120M, 6 S., (2011)

Russbueldt, P., Hoffmann, H.-D., Mans, T., Poprawe, R.:
1100 W Yb:YAG femtosecond Innoslab amplifier
Proc. SPIE 7912, 79120R, 9 S., (2011)

Schulz, M., Riedel, R., Willner, A., Mans, T., Schnitzler, C., Russbueldt, P., Dolkemeyer, J., Seise, E., Gottschall, T., Hädrich, S., Duesterer, S., Schlarb, H., Feldhaus, J., Limpert, J., Faatz, B., Tünnermann, A., Rossbach, J., Drescher, M., Tavella, F.:
Yb:YAG Innoslab amplifier: efficient high repetition rate subpicosecond pumping system for optical parametric chirped pulse amplification
Opt. Lett. 36, Nr. 13, 2456-2458, (2011)

Weitenberg, J., Rußbüldt, P., Eidam, T., Pupeza, I.:
Transverse mode tailoring in a quasi-imaging high-finesse femtosecond enhancement cavity
Opt. Expr. 19, Nr. 10, 9551-9561, 2011

Rußbüldt, P., Mans, T., Weitenberg, J., Hoffmann, H. D., Poprawe, R.
Compact diode-pumped 1.1 kW Yb:YAG Innoslab femtosecfond amplifier
Opt. Lett. 35; Nr 24, 4169-4171, (2010)

B. Gronloh, M. Höfer, R. Wester, H.-D. Hoffmann
High power UV generation at 355 nm by means of extracavity frequency conversion of a high repetition rate Innoslab MOPA system
Proc. SPIE 7193, 71930Y, 11S., (2009)

T. Mans, P. Rußbüldt
Höchste mittlere Leistung für Ultrakurzpulslaser
LASER+PHOTONIK Nr. 3, 20-24, (2009)

D. Wortmann, T. Mans, J. Weitenberg
Multi-100 W average power fs-laser for material processing applications
ICALEO 2009, 28th Int. Congr. on Applications of Lasers & Electro-Optics, November 2-5, 2009, Orlando, Fl.
paper M101, pp. 856-860, (2009)

M. Mir, N. Gutknecht, R. Poprawe, L. Vanweersch, F. Lampert
Visualising the procedures in the influence of water on the ablation of dental hard tissue with erbium:yttrium-aluminium-garnet and erbium, chromium:yttrium-scandium-gallium-garnet laser pulses
Lasers Med. Sci. 24, 365-374, (2009)

T. Mans, P. Rußbüldt, Weitenberg, J.
Yb :KYW Innoslab-Amplifier
Conference on Lasers and Electro-Optics 2009 and the European Quantum Electronics Conference. CLEO Europe - EQEC 2009, Munich, 14-19 June 2009
Mulhouse: European Physical Society
paper CA3_2, 1 S., (2009)

P. Rußbüldt, T. Mans, G. Rotarius, J. Weitenberg, H.D. Hoffmann, R. Poprawe
400 W Yb:YAG Innoslab fs-amplifier
Opt. Expr.
17, Nr 15, 12230-12245, (2009)

P. Rußbüldt, T. Mans, D. Hoffmann, R. Poprawe
High Power Yb:YAG Innoslab fs-Amplifier
Proceedings of the Conference on Lasers and Electro-Optics & Quantum Electronics and Laser Science Conference (CLEO), May 4-9, 2008, San Jose, California
Vortrag CTuK5, 2 S., (2008)