The improvement of peak power of femeto-laser depends on the compression of pulse width. The titanium-doped sapphire crystal is the excellent laser crystal with the shortest pulse width. Its theoretical pulse width limit is 3 fs. At present 50-TW tabletop Ti:sapphire lasers have been commercialized. In this paper, comparison of Ti:sapphire crystals grown by temperature gradient technology (TGT) and heat exchange method (HEM) is presented, and results show that the laser quality of Ti:sapphire crystals grown by TGT is similar to or higher than those grown by HEM. circle divide 10-30mm, high optical homogeneity Ti:sapphire amplifiers were fabricated successfully and 5-40TW high power were obtained. We believe that up to 0 100 Ti:sapphire amplifiers (grown by TGT) can be obtained for ultrahigh power laser systems using all Ti:sapphire crystals. in near future. (C) 2003 Elsevier B.V. All rights reserved.