The development of every technology experiences an initially crude stage. Compared to globars, synchrotrons or quantum cascade lasers which are technologically mature, the achievements using SC generation are in many respects in their infancy. In many cases the fibers or waveguides used in our experiments were prototypes: the first of their kind and there is room for much improvement in their losses, in the optimization of materials and methods for fabrication. The pump source itself is quite complex but for MIR SC long wavelength pumps seem inevitable. The OPA based source we employed is certainly much simpler than the alternative in the form of synchronously- pumped OPOs, however, it remains a rather costly component in the overall system. Fortunately there are some ways ahead. The MIR OPA can be operated as a waveguide device and this has been confirmed in our laboratory. Combined with a fiber laser and integrated planar waveguide for SC generation such an approach could lead to substantial reductions in cost and complexity. Nevertheless, such developments are far from trivial and will take much effort to achieve. However, no gain is achieved without effort, and perhaps the results presented here show that the effort is justifiable. That is how we as the human race advance.
I feel lucky that I was part of this pursuit for creating something bigger than myself. For the love of mid-infrared, supercontinuum and chalcogenides.
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