Watt-level 193 nm source generation based on compact collinear cascaded sum frequency mixing configuration

A compact, dual-stage, collinear-cascaded sum-frequency mixing configuration is presented for generating 193 nm sources. Due to the less-introduced, deep-ultraviolet optical components, the system is less prone to damage. In our proof-of-concept experiments, a 1030 nm laser and a 1553 nm laser synchronized to each other were used as drivers and an average power of ~0.7 W was obtained. For comparison, the noncollinear configuration gave an average power of 0.77 W. The difference of 0.07 W is attributed to the spatial walk-off inside the cesium lithium borate (CLBO) crystal, confirmed by indirect visualization. A possible way to overcome the small gap of 0.07 W is proposed for future work.