Nanocarbon-integrated compact ultrafast solid-state lasers
  • prof. Fabian Rotermund
  • SLS Colloquia / Dec 6th 04:00 pm / BLDG.110 ROOM N104
Abstract

Low-dimensional nanocarbons such as graphene and carbon nanotubes (CNTs) have been widely used for various photonic applications in recent years. One of the most successful approaches seems to be their applications as broadband saturable absorbers (SAs) in ultrafast laser systems. As known, Q-switching or mode-locking by employing appropriate SAs is the widely used technique for pulsed laser operation. Graphene and CNTs exhibit broadband absorption with large and ultrafast third-order nonlinearities and require relatively simple fabrication processes. They provide an efficient nonlinear optical switching mechanism with ultrafast responses enabling applications for developing diverse ultrafast lasers. Compared to widespread semiconductor saturable absorber mirrors (SESAMs), graphene-based SAs exhibit superior advantages of ultrafast saturable absorption over an ultrabroad spectral region, even far beyond 2 mm without additional bandgap engineering due to the unique point-bandgap structure of graphene and the linear dispersion of Dirac electrons, while the applicable wavelength and spectral bandwidth of CNT-based SAs can be controlled by chirality and diameter of CNTs distributed in the absorber layer.

In this talk, nanocarbon-integrated compact mode-locked and Q-switched solid-state (bulk, fiber and waveguide) lasers operating in different spectral regions will be reviewed and possible applications of such lasers for bio-photonic will be also discussed.