High-average-power light source below 200 nm from a KBe_(2)BO_(3)F_(2) prism-coupled device

摘要

Using a 2.3 mm thick KBe_(2)BO_(3)F_(2) crystal optically contacted with CaF_(2) in a prism-coupled device, we have obtained an average output power of as much as 360 mW at 200 nm. Long-term stability was verified above a 150 mW level at 200 nm. An output power of 50 mW was also obtained with a narrow spectral width of 0.007 pm at 193.5 nm.