Phase-matched third-harmonic generation from nematic liquid crystals

Abstract

The type-II phase-matching condition of the direct third-harmonic generation originated from third-order nonlinearity (3ω=ω+ω+ω) is performed in nematic liquid crystals with a fundamental light at 1064 nm. Since the phase-matching condition can be achieved in normal incidence of the fundamental light, the walk-off angle is zero. Thus, the interaction length is equal to the thickness of the liquid crystal film. Although the conversion efficiency in the present system is still low, 9.1×10−8, it will become 10−2 as discussed in this letter.