Andermahr N, Fallnich C
Laser Zentrum Hannover, Hollerithallee 8, 30419 Hannover, Germany.
Opt Express. 2008 Jun 9;16(12):8678-84. doi: 10.1364/oe.16.008678.
We report on the behavior of modal polarization states in a single-frequency, ytterbium-doped, few-mode fiber amplifier. Experimental data show that the polarization of the individual transverse modes depends on the pump power and that the modes tend towards orthogonally polarized states with increasing gain. The observations can be explained by local gain saturation that favors the amplification of differently polarized modes.
