The exponential gain of two-beam coupling in lnP:Fe crystals under dc fields is a function of the pump beam intensity at a given temperature. We propose two methods to extend the sample volume working under optimum conditions. The first method is based on a negative thermal gradient and the second uses an auxiliary incoherent beam. Theoretical simulations predict an integrated gain of l5 cm^-1 and 10 cm^-1, respectively (for λ = 1.06 μm. Λ = 5 μm and E₀ = 10 kV/cm) in thick crystals (L = 5 mm). Preliminary experimental results confirm that high gain performances can be achieved by using these methods.

Date Published: 1 April 1991
PDF: 6 pages
Opt. Eng. 30(4) doi: 10.1117/12.55820
Published in: Optical Engineering Volume 30, Issue 4