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室温下采用640 nm的飞秒脉冲激光泵浦ZnO纳米针得到双光子诱导的光致发光谱.结合单光子下的研究结果,实验分析了双光子泵浦下样品随着受激能量增强产生的三种紫外发射行为并归结为自由激子自发辐射,激子-激子散射和电子空穴等离子体复合.双光子泵浦下ZnO纳米针的受激阈值是4.82 GW/cm~2,远小于其他ZnO微纳材料的双光子阈值(TW/cm~2).结果表明:这种新型的ZnO纳米针结构能更有效地产生双光子激射,这在纳米激光器方面将会有很大的应用前景.“,”Stimulated emissions in a novel nanoneedle ZnO composite with two complex needle parts were investigated using the two-photon induced time-resolved photoluminescence pumped with the femtosecond pulse at the wavelength of 640 nm in room temperature. Comparing with the results of single-photon pumped, we observe three operation mechanisms of two-photon induced UV emission behaviors with the excitation power increasing:spontaneous emission of free-exciton, exciton-exciton(E-E) scattering and electron-hole-plasma (EHP) recombination. The threshold of two-photon excitation emission is 4.82 GW/cm~2,which is far lower than that of mirconeedle ZnO reported recently and the other nanostructure of ZnO(TW/cm~2).Our research results proved that the new ZnO nanoneedle structure with UV emission efficiently induced two-photon shows great potential applications in the two-photon induced nanolasers fields.