Continuous wave simultaneous multi-self-frequency conversion in Nd³⁺-doped aperiodically poled bulk lithium niobate

We report simultaneous participation of the fundamental laser wave in self-frequency doubling and self-sum-frequency mixing with pump radiation in Nd³⁺-doped bulk aperiodically poled lithium niobate structures. A green continuous wave visible laser output power of 1.5 mW generated by self-frequency doubling and 0.5 mW of blue generated by self-sum-frequency mixing have been obtained simultaneously from 30 mW of laser output power available in the fundamental. Stable and efficient infrared laser action at room temperature is obtained in both ⁴F_3/2→⁴I_11/2 and ⁴F^3/2 →⁴I_13/2 laser channels of Nd³⁺ ion without oxide codoping, although some residual photorefractive damage for the visible outputs is observed.