High Energy, Low Loss Fibers for Ultra Short Pulse Laser Compression and Delivery

Raydiance and the Massachussets Institute of Technology are proposing to investigate hollow core photonic bandgap fibers and related waveguide architectures for pulse compression and delivery of ultrashort high peak power pulses. Photonic bandgap fibers, and especially Bragg fibers, are particularly well suited for pulse compression and delivery of high peak power pulses due to low loss hollow core waveguiding capability as well as predicted large waveguide dispersion. Another feature of 1D photonic bandgap fiber, or Bragg fiber, is the ability to maintain single mode propagation with large mode area. Preliminary experiments conducted by Raydiance, Inc. indicate that single mode propagation can be obtained for hollow core mode field diameters of 100 μm and that such fibers can withstand 1 ps pulses with 4 μJ of energy per pulse. In Phase I of this program, Raydiance and MIT will model and compare various waveguide geometries and investigate dielectric materials in order to reduce losses and increase waveguide dispersion of existing photonic bandgap fibers. Appropriate waveguide geometries, materials and fabrication processes needed to compress and deliver 10 MW peak power pulses will be determined after completion of Phase I.