Optimizing single mode robustness of the distributed modal filtering rod fiber amplifier

Optimizing single mode robustness of the distributed modal filtering rod fiber amplifier.

High-power fiber amplifiers for pulsed applications require large mode area (LMA) fibers having high pump absorption and near diffraction limited output. Photonic crystal fibers allow realization of short LMA fiber amplifiers having high pump absorption through a pump cladding that is decoupled from the outer fiber diameter. However, achieving ultra low NA for single mode (SM) guidance is chall...

Cross-correlated imaging of single-mode photonic crystal rod fiber with distributed mode filtering.

Photonic crystal bandgap fibers employing distributed mode filtering design provide near diffraction-limited light outputs, a critical property of fiber-based high-power lasers. Microstructure of the fibers is tailored to achieve single-mode operation at specific wavelength by resonant mode coupling of higher-order modes. We analyze the modal regimes of the fibers having a mode field diameter o...

Single-mode Fiber Length for Wavefront Filtering

Stellar nulling interferometry offers the possibility of direct imaging of extrasolar planets necessary for the detection of extra-terrestrial life. Achieving optimum performance from the interferometers requires that the wavefronts of light reaching the interferometer are free of distortions. This is achieved by using single-mode fibers, which are excellent wavefront filters. In this paper, we...

Mode-Filtered Fiber Amplifier

Single-mode operation of a coiled multimode fiber amplifier.

We report a new approach to obtaining single-transverse-mode operation of a multimode fiber amplifier in which the gain fiber is coiled to induce significant bend loss for all but the lowest-order mode. We demonstrated this method by constructing a coiled amplifier using Yb-doped, double-clad fiber with a core diameter of 25 microm and a numerical aperture of ~0.1 (V approximately 7.4) . When t...