Vertical-external-cavity surface-emitting lasers (VECSELs) combine semiconductor gain media with cavity design as it is typical for solid-state lasers. Hence, they are also referred to as semiconductor disk lasers (SDL). They are extremely versatile and potentially high power devices with excellent beam quality (brightness converters). Experiments concerned

  • mode-locking of VECSELs at low repetition rates as required in biophotonics by synchronous pumping,
  • in-well pumping of VECSELs.

News and esteem

  • Invited talk: Extending the wavelength coverage of VECSELs.
    Advanced Semiconductor Material Workshop, Tucson, AZ, February 20-21, 2008.
  • Invited talk: Vertical-cavity external surface-emitting lasers – An overview and specific aspects.
    Coherent Engineering Seminar, Coherent Inc., Santa Clara, CA, USA, Aug 12, 2011.


  • C. Bueckers, E. Kuehn, C. Schlichenmaier, S. Imhof, A. Thraenhardt, J. Hader, J. V. Moloney, O. Rubel, Wei Zhang, T. Ackemann, and S. W. Koch.
    Quantum modelling of semiconductor gain materials and vertical-external-cavity surface-emitting laser systems.
    Phys. stat. sol. (b) 247, 789 (2010)
  • Wei Zhang, A. McDonald, T. Ackemann, E. Riis, G. McConnell.
    Femtosecond synchronously in-well pumped vertical-external-cavity surface-emitting laser.
    Opt. Exp. 18, 187 (2010)
  • Wei Zhang, T. Ackemann, S. McGinily, M. Schmid, E. Riis, A. I. Ferguson.
    Operation of an optical in-well-pumped vertical-external-cavity surface-emitting laser.
    Appl. Opt. 45, 7729 (2006)
  • Wei Zhang, T. Ackemann, M. Schmid, N. Langford, A. I. Ferguson.
    Femtosecond Synchronously Mode-locked Vertical-External Cavity Surface-Emitting Laser.
    Opt. Exp. 14, 1810 (2006)