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Project TitleAll-normal-dispersion Femtosecond Fiber Laser
Track Code3963
Short Description

This new all-normal dispersion (ANDi) fiber laser avoids the complications of compensating group-velocity dispersion (GVD) in femtosecond fiber lasers.


It is easy to manufacture, reliable and efficient, and is the first all-fiber laser that can directly replace a Ti-Sapphire laser in many applications. Prototypes suitable for use in terahertz imaging applications have been built.


Group-velocity dispersion (GVD) is a ubiquitous problem in femtosecond lasers. Prisms, diffraction gratings, microstructure fibers, and chirped mirrors have all been used to compensate GVD in ytterbium fiber lasers, but these are bulky, lossy, expensive, or introduce performance sacrifices.


The ANDi laser is a mode-locked fiber laser that features a new approach to pulse-shaping, based on spectral filtering of a highly-chirped pulse. The ANDi lasers cavity consists only of elements with normal GVD. There is no dispersion control in the cavity. By increasing the nonlinear phase shift accumulated by the pulse and inserting a spectral filter in the cavity, the laser is able to produce pulses with notable improvements in energy. The laser generates picosecond pulses, which are dechirped to the transform limit outside the laser. The pulse evolution in an ANDi laser fundamentally allows the highest possible stable pulse energy. 150-femtosecond pulses with energy as high as 25 nJ can be generated. Pulses as short as 75 femtoseconds have also been generated, with energy of 5 nanojoules. Thus, the ANDi laser offers performance comparable to that of solid-state lasers, but with the major benefits of fiber: reduced cost, alignment-free operation, increased stability, and compact construction.


Potential Applications

  • Nano surgery
  • Dentistry
  • Cancer treatments
  • Precision cutting
  • Guidance systems
  • High-speed measurements
  • Bio-imaging with nonlinear microscopies (multiphoton, CARS, etc.)
  • Terahertz systems 



  • Higher energy pulses
  • Simple and stable
  • More compact
Tagsfiber optics, lasers, Optics & Photonics, physical science
Posted DateJul 23, 2012 5:58 PM


Chin (Andy) Chong
Joel Buckley
Frank Wise

Additional Information

Licensing Contact

Patrick Govang

(607) 254-2330