摘要
用提拉法成功生长出3种不同掺Eu^3＋浓度的优质Yb，Er，Eu：YAP激光晶体，并对其光谱特性进行了研究。测量了晶体在320～3000nm波段内的吸收光谱，晶体在978nm附近有强的吸收峰和宽的吸收带。用波长为975nm的LD连续激光和OPO光参量脉冲激光激发分别获得了晶体的稳态和瞬态荧光光谱，采用单指数衰减拟合得到2．7～3．0μm激光上下能级寿命。与单掺Er：YAP晶体的光谱参数进行了比较，对Yb^3＋的敏化及Eu^3＋的退激活机理进行了分析。结果表明，Yb3＋和Eu^3＋可分别作为Er抖的敏化剂和退激活剂，增宽978nm附近的吸收带和降低激光下能级（4I13／2）与上能级（4I11／2）寿命的比值（4．1，3．1和2．7）；而在单掺Er：YAP晶体，下能级与上能级寿命的比值高达10．8，不利于激光性能的提高。因此，Yb，Er，Eu：YAP是一种更适合LD泵浦，有望实现低阈值、2．7～3．0μm高效率激光输出的新型激光晶体。
Abstract：We report the Yb,Er,Eu：YAP laser crystals with three different Eu^3＋ doping concentrations grown by the Czochralski method and investigate their spectroscopic characteristics. The absorption spectrum in the range of 320-3 000 nm is measured, and there is strong absorption and wide absorption band around 978 nm. The fluorescence spectrum and decay curves are measured by the excitation of 975 nm LD and OPO laser,respectively. The level lifetime is obtained with single exponential decay. These parameters are compared with those of the single doped Er： YAP crystal and the sensitization and deacti- vation mechanisms are analyzed. The results indicate that the Yb^3＋ and Eu^3＋ ions can act as sensitizer and deactivator for Er^3＋ ions, respectively, resulting in the widening of the absorption band at 978 nm and decreasing of the lifetime ratio （4. 1,3.1 and 2.7） between the lower laser level （4 I13/2 ） and upper laser level （4 I11/2）. However,the lifetime ratio of single doped Er.. YAP is very high and up to 10.8, which is disadvantageous to the improvement of the laser output properties. Therefore, the new Yb, Er, Ho.YAP laser crystal is more suitable to be pumped by 970-980 nm LD laser and the 2.7-3.0μm laser output could be realized easily with lower laser threshold and higher laser conversion efficiency.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2014年第3期491-495,共5页
Journal of Optoelectronics·Laser
基金
国家自然科学基金(91122021
51272254
61205173
51172236和50932005)资助项目
关键词
激光晶体
吸收系数
光谱
寿命
laser crystal
absorption coefficient
spectra
lifetime
