Mode-locked Fiber Lasers and Their Applications

Brian Richard Washburn

National Institute of Standards of Technology

325 Broadway, Boulder CO

email: brianw@boulder.nist.gov

Abstract:

Mode-locked femtosecond lasers have made a tremendous impact on the fields of ultrafast physics and nonlinear optics.  This is due to the utility of the large energy, short duration optical pulses produced from these lasers.  In fact, femtosecond lasers are current being used for applications including laser machining, medical imaging, surgery, and optical frequency measurements.  Recently, mode-locked lasers constructed entirely using fused-silica optical fiber has demonstrated pulse powers and durations that are comparable to the output of traditional solid-state lasers.  This is significant since a fiber laser has many advantages over a solid-state laser in terms of size and cost.  For instance, a fiber laser consumes less power and can exploit the large range of available telecommunication technologies. 

This colloquium will begin with the general theory and operation of passively mode-locked Erbium-doped fiber lasers.  This will include a discussion on the basic physics that occurs in optical fiber that cause the laser to produce femtosecond optical pulses.  Then, I will illustrate how a mode-locked fiber laser can be used for precision frequency measurements.  This will include a description of two all-fiber based supercontinuum sources that were developed at NIST.  The talk will conclude with interesting applications of mode-locked lasers in the fields of remote sensing, high-energy physics, and radio astronomy.