19 May 1998 Fiber phase conjugators for high-power lasers
Author Affiliations +
Using stimulated Brillouin-scattering (SBS) in glass fibers as phase-conjugating process, the field of application of SBS phase-conjugators can be expanded, because fibers offer a decreased power threshold and a stable behavior even at high input powers. We have developed phase conjugators consisting of multimode fused silica fibers in standard or tapered geometry with core diameters between 25 and 400 μm. Such fiber phase conjugators were characterized for different lengths in respect of the phase conjugating parameters like threshold, reflectivity, and fidelity. Dependencies of all SBS parameters on the fiber length and on the coherence length of the input beams were determined. Such optimized fiber phase conjugators operate with more than 50% reflectivity, 93% fidelity, and less than 200 W threshold in the spectral range from IR down to the UV. A depolarization of SBS pulses could be reduced to less than 0.3% by proper configuration of the fiber. High power densities of more than 1 GW/cm2 do not damage our fiber phase conjugators, because the absorption of the fiber materials used is very low. Furthermore, fiber phase conjugators are harmless to the environment and beat the performance of dangerous liquid or high pressure gas SBS- cells used in high power lasers up to now in all concerns. High economic benefits can be expected due to the popular fiber materials used from the glass fiber technology.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Hans Joachim Eichler, Baining Liu, Andreas Haase, Oliver Mehl, A. Dehn, "Fiber phase conjugators for high-power lasers", Proc. SPIE 3263, Nonlinear Optical Engineering, (19 May 1998); doi: 10.1117/12.308359; https://doi.org/10.1117/12.308359

Back to Top