Fiber Laser
PublicationsOptical Damage
Thermal Lensing
Self-focusing
Self-phase modulationStimulated Brillouin Scattering
Gain ModelsStimulated Raman Scattering
Mode Calcuations (including bent fibers)

Fiber lasers/amplifiers offer advantages over bulk lasers in efficiency, beam quality, thermal management, and packaging flexibility. The can be based on different lasing ions including ytterbium, erbium, thulium which operate in different wavelength ranges. Fiber lasers can operated mode locked in the femto-pico second range or CW or Q-switched in the nanosecond range. Large core diameters and double cladding make possible CW powers of kW and pulsed peak powers of MW.

Numerical models are invaluable In optimizing a fiber laser or amplifier. We have models that compute mode profiles including bending and arbitrary refractive index profiles. We also have gain models the predict performance based on pump power and spectrum, fiber length, operating wavelength, etc. Nonlinear processes such as stimulated Brillouin scattering (SBS), stimulated Raman scattering (SRS), four-wave mixing (4WM), self phase modulation (SPM), self focusing, and optical damage set limits on power and pulse width.

The figures below illustrate some of our modeling results for pulse amplification in a Yb-doped fiber amplifier.

We offer modeling that includes mode profiles, pump properties, fiber properties, and nonlinear processes. We can model CW to femto second, and nW to MW operation. Our models have been benchmarked against laboratory measurements with excellent agreement. We can help analyze on novel designs, trouble shoot problems, and advise on how to avoid nonlinear problems such as SBS and SRS.

 


Amplified Spontaneous Emission from the two ends of a fiber amplifier operating at 5,000 pulses per second.
Irradience profile in a bent, 60 micron diameter core fiber. The mode is displaced toward the outside of the bend.
Some low order transverse modes of an unbent multimode fiber.