Abstract

Several groups have demonstrated the production of sub-20 fs pulses using a modelocked Ti:Al₂O₃, laser with reduced third order dispersion.^1-3 These pulse durations have been achieved by choosing a suitable prism material or reducing the length of the Ti:Al₂O₃ rod. The optimal choice of prism material is quartz. However, given the spacing constraints the laser resonator places on the prism separation, a pair of quartz prisms has only been demonstrated in a Ti:Al₂O₃ laser with a 4-mm rod.^2,3 The use of such a short rod may compromise both gain and nonlinearity. We have demonstrated that a sequence of four quartz prisms can provide large negative second-order dispersion while having a small residual cubic phase.⁴

© 1993 Optical Society of America