Terawatt diode-pumped Yb: CaF2 laser

We present what we believe to be the first terawatt diode-pumped laser employing single-crystalline Yb:CaF2 as the amplifying medium. A maximum pulse energy of 420 mJ at a repetition rate of 1 Hz was achieved by seeding with a stretched femtosecond pulse 2 ns in duration, preamplified to 40 mJ. After recompression, a pulse energy of 197 mJ and a duration of 192 fs were obtained, corresponding to a peak power of 1 TW. Furthermore, nanosecond pulses containing an energy of up to 905 mJ were generated without optical damage. (C) 2008 Optical Society of America