Enhancing the upconversion luminescence of rare earth ions is crucial for their applications in the laser sources,fiber optic communications,color displays,biolabeling,and biomedical sensors.In this paper,we theoretic...Enhancing the upconversion luminescence of rare earth ions is crucial for their applications in the laser sources,fiber optic communications,color displays,biolabeling,and biomedical sensors.In this paper,we theoretically study the resonance-mediated(1+2)-three-photon absorption in Pr^(3+) ions by a rectangle phase modulation.The results show that the resonance-mediated(1+2)-three-photon absorption can be effectively enhanced by properly designing the depth and width of the rectangle phase modulation,which can be attributed to the constructive interference between on-resonant and near-resonant three-photon excitation pathways.Further,the enhancement efficiency of resonance-mediated(1+2)-threephoton absorption can be affected by the pulse width(or spectral bandwidth)of femtosecond laser field,final state transition frequency,and absorption bandwidths.This research can provide a clear physical picture for understanding and controlling the multi-photon absorption in rare-earth ions,and also can provide theoretical guidance for improving the up-conversion luminescence.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12004238 and 11764036)the Natural Science Foundation of Henan Province,China(Grant No.222102230068)the Open Subject of the Key Laboratory of Weak Light Nonlinear Photonics of Nankai University(Grant No.OS 21-3)。
文摘Enhancing the upconversion luminescence of rare earth ions is crucial for their applications in the laser sources,fiber optic communications,color displays,biolabeling,and biomedical sensors.In this paper,we theoretically study the resonance-mediated(1+2)-three-photon absorption in Pr^(3+) ions by a rectangle phase modulation.The results show that the resonance-mediated(1+2)-three-photon absorption can be effectively enhanced by properly designing the depth and width of the rectangle phase modulation,which can be attributed to the constructive interference between on-resonant and near-resonant three-photon excitation pathways.Further,the enhancement efficiency of resonance-mediated(1+2)-threephoton absorption can be affected by the pulse width(or spectral bandwidth)of femtosecond laser field,final state transition frequency,and absorption bandwidths.This research can provide a clear physical picture for understanding and controlling the multi-photon absorption in rare-earth ions,and also can provide theoretical guidance for improving the up-conversion luminescence.
