Enhancement of two-wave coupling in a Ce:KNSBN crystal with optimum polarization of the writing beams
2001
We have improved the two-wave coupling amplification and the
signal-to-noise ratio of an amplified signal with photorefractive
cerium-doped potassium sodium strontium barium niobate (Ce:KNSBN)
by employing optimum polarization orientation of the pump beam while
the signal beam retains extraordinary polarization. The optimum
polarization angle of the pump beam was found experimentally to be
30° with respect to the extraordinary polarization direction in a
symmetrically incident system. Nearly 1.9-times enhancement of the
gain and nearly 3-times enhancement of the signal-to-noise ratio were
achieved at a signal-to-pump beam intensity ratio of 1:40. At a
beam intensity ratio of 1:2000, a two-wave coupling gain of nearly 500
was obtained, which is much higher than the gain previously
reported. Modified coupled-wave equations that involve beam fanning
with certain assumptions concerning the fanning parameters were
used. The numerical solution is in good agreement with the
experimental data. The results are compared with those obtained
with a 45°-cut BaTiO3 crystal.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
14
References
3
Citations
NaN
KQI