一种新型有机染料HEASPS的激光上转换和光限幅性能

报道了一种新型上转换染料———反式 4 [4’ (N 羟乙基 N 乙基胺基 )苯乙烯基 ] N 甲基吡啶 对甲苯磺酸盐(trans 4 [4’ (N hydroxyethyl N ethylamino)styryl] N methylpyridiniump toluenesulfonate ,简称HEASPS)DMF溶液的激光上转换性质和光限幅性质。用Z 扫描技术测得其双光子吸收截面为σ2 =4.7× 10 -4 8cm4 ·s/photon ,研究了它在DMF溶剂中的线性吸收、单光子荧光、双光子荧光和双光子激射特性 ,用再吸收效应解释了双光子荧光峰相对单光子荧光峰的红移现象 ,该染料的激射和再吸收现象相互竞争导致了双光子激射峰相对于双光子荧光峰的蓝移现象。在 10 6 4nm皮秒脉冲激光的激发下 ,可得强烈的 6 2 6nm上转换激射光 ,上转换效率最高为 15 .5 % ,从抽运光到激射光的净转换效率为 2 6 %。该染料的DMF溶液表现出明显的光限幅特性

Upconversion Lasing and Optical Power Limiting Properties of a New Organic Dye HEASPS

The upconversion and optical power limiting properties of a new organic dye trans 4 [4' (N hydroxyethyl N ethylamino)styryl] N methylpyridinium p toluene sulfonate (abbreviated as HEASPS thereafter) in DMF are reported in this paper. The two photon absorption cross section of HEASPS at 1064 nm is measured to be σ 2=4.7×10 -48 cm 4·s/photon by using a Z scan system. The linear absorption, single photon induced fluorescence, two photon induced fluorescence and two photon pumped upconversion lasing properties are studied. There is a red shift for the central wavelength of the two photon induced fluorescence compared with that of the single photon induced fluorescence and a blue shift for two photon induced lasing compared with two photon induced fluorescence. These phenomena can be explained by using the re absorption effect. Intense upconversion lasing at 626 nm is obtained pumped by a mold locked Nd:YAG ps pulse laser operating at 1064 nm. The upconversion efficiency from the pump efficiency from the absorbed energy to the upconversion energy is 26%.