Widely and continuously tunable optical parametric oscillator based on a cylindrical periodically poled KTiOPO_4 crystal

We report on what is to our knowledge the first realization of a quasi-phase-matched optical parametric oscillator (OPO) based on a crystal with a cylindrical shape. The main reason for interest in this device is its broad, continuous tuning. In experiments with a 1064-nm pump, the signal tuning range was equal to 525 nm (1515-2040 nm), and the corresponding idler was continuously tuned over 1340 nm (2220-3560 nm). The angular tuning was 26 degrees , with only a minor variation of the OPO threshold over the entire tuning range.