Abstract

The Earth's atmosphere, consisting of SBS-active nitrogen and oxygen, can be considered as nonlinear optical medium in which excitation of SBS with accompanying phase conjugation is possible. The main factors hindering this are (i) low threshold of optical breakdown because of impurities presence in natural atmosphere and (ii) high SBS threshold because of turbulent distortions of a pump beam. One work is known only in which SBS of a diffraction quality laser beam was registered at a level of 0.1% from the pump power when focusing in a cell with pure nitrogen at a pressure of 1 atm /1/.

© 1996 IEEE