arXiv:1310.0712 · Optics Letters
Weak-signal conversion from 1550 to 532 nm with 84% efficiency
Aiko Samblowski, Christina E. Vollmer, Christoph Baune, Jaromı́r Fiurášek, Roman Schnabel
Abstract
We report on the experimental frequency conversion of a dim, coherent continuous-wave light field from 1550 to 532 nm with an external photon-number conversion efficiency of (84.4±1.5)%. In contrast to previous works, our conversion efficiency value incorporates all losses before the photoelectric detection, including those introduced by frequency filters. We used sum-frequency generation, which was realized in a standing-wave cavity built around a periodically poled type I potassium titanyl phosphate (PPKTP) crystal, pumped by an intense field at 810 nm. Our result is in full agreement with a numerical model. For optimized cavity coupler reflectivities, it predicts a conversion efficiency of up to 93% using the same PPKTP crystal.