A fully tunable dual-color CW Ti:Al/sub 2/O/sub 3/ laser

We introduce a CW two-color Ti:sapphire laser for terahertz spectroscopic applications. The laser provides two parallel beams at independently tunable wavelengths allowing one to select a difference frequency in the range from below 20 GHz to 50 THz. The laser is pumped by a single 6-W pump beam in order to keep the setup as simple as possible. Under these conditions, output powers of 150 mW per beam in the gain-maximum region are achieved.