Investigation of thermally-induced phase mismatching in continuous-wave second harmonic generation: a theoretical model

• DOI: 10.1364/oe.18.018732
• Publication Date: 2010-08-18T19:12:19Z
• Authors: Mohammad Sabaeian; Laleh Mousave; Hamid Nadgaran
• Keywords: Crystal (programming language); Temperature Gradient; Continuous wave

A fraction of the fundamental beam energy deposited into nonlinear crystals to generate second harmonic waves (SHW) causes a temperature gradient within crystal. This inhomogeneity can alter refractive index medium leading well-known effect called thermal dispersion. Therefore, generated SHW suffers from lensing and longitudinal phase mismatching. In this work by coupling heat equation with generation (SHG) formalism applied type-II configuration along walk-off effect, we investigate continuous wave (CW) profile conversion efficiency when non-linear KTP crystal is under induced load. We have demonstrated for average high powers, de-phasing lead considerable reduction in SHG compared an ideal case which neglected.