设计并研制了一种基于复合腔结构的波长可调谐、瓦级连续输出的橙红色激光器.该激光器是由半导体激光侧泵Nd∶GdVO4晶体产生p-偏振1 062.9 nm基频光的谐振腔和使用周期性极化晶体MgO∶PPLN(三个极化周期为29.0 μm、29.8 μm和30.8 μm)的单共振光学参量振荡器组成.在两个谐振腔的重叠区域, 利用II类临界相位匹配KTP晶体对s-偏振信号光与p-偏振1 062.9 nm基频光进行腔内和频.通过对MgO∶PPLN晶体进行三个不同极化周期的调谐和30℃~200℃范围内的温度调谐, 在三个波段(613.4~619.2 nm@29.0 μm、620.2~628.9 nm@29.8 μm和634.4~649.1 nm@30.8 μm)获得了波长可调谐的橙红色激光连续输出, 并在相应波段(3 980.0~3 758.5 nm @29.0 μm、3 714.2~3 438.3 nm @29.8 μm和3 278.0~2 940.2 nm @30.8 μm)获得了波长可调谐的中红外闲频光的连续输出.在30℃最低调谐温度, 通过改变晶体的极化周期, 在613.4 nm、620.2 nm和634.4 nm处测得最大连续输出功率分别为1.52 W、2.21 W和3.03 W, 对应的三束闲频光最大连续输出功率分别为2.36 W @3 980.0 nm、3.17 W @3 714.2 nm和4.13 W @3 278.0 nm.

An orange-red laser was designed and developed based on a composite cavity structure with tunable wavelength, W-level continuous output. It consisted of a resonant cavity which generated p-polarized 1 062.9 nm fundamental frequency light based on laser diode side pumped Nd∶GdVO4 crystal and a single resonant optical parametric oscillator using a periodically poled crystal MgO∶PPLN with three-poling periods (29.0 μm, 29.8 μm, and 30.8 μm). In the overlap region of the two resonant cavities, the type-II critical phase-matched crystal KTP was used to bring about inner-cavity sum-frequency generation with the s-polarized signal light and the p-polarized 1 062.9 nm fundamental frequency light. By the tuning of three different polarizations of MgO∶PPLN crystal and the temperature tuning in the range of 30℃~200℃, the wavelength tunable orange-red laser with W-level continuous outputs in three bands(613.4~619.2 nm at 29.0 μm, 620.2~628.9 nm at 29.8 μm and 634.4~649.1 nm at 30.8 μm) were obtained. In addition, the wavelength tunable mid-infrared idlers were gained in the corresponding bands(3 980.0~3 758.5 nm at 29.0 μm, 3 714.2~3 438.3 nm at 29.8 μm and 3 278.0~2 940.2 nm at 30.8 μm). By changing the poling periods at 30℃ minimum temperature, the maximum continuous output powers were measured as 1.52 W (at 613.4 nm), 2.21 W (at 620.2 nm) and 3.03 W (at 634.4 nm). At the same time, the maximum continuous output powers of the three corresponding idlers were measured as 2.36 W(at 3 980.0 nm), 3.17 W(at 3 714.2 nm) and 4.13 W(at 3 278.0 nm), respectively.