EFFICIENT GENERATION OF ULTRAVIOLET-RADIATION BY TANGENTIAL PHASE-MATCHING

Tangential phase-matching is analysed for short wavelength generation by type-I sum-frequency mixing and frequency doubling using a Nd:YAG laser and its second-harmonic pumped dye laser in beta barium borate crystal. An increase in angular tolerance over one of the interacting beams by an order of magnitude has been obtained. A comparison of conversion efficiencies between interaction under critical non-colinear phase-matching and tangential non-colinear phase-matching has been made under focusing of one of the input beams over which a large tolerance exists. Thereby the importance of tangential phase-matching in increasing conversion efficiency by an order of magnitude over that of critical non-collinear phase-matching has been verified.