Visible light microlasers are essential building blocks for integrated photonics.However,achieving low-threshold(μw),continuous-wave(CW)visible light lasing at room temperature(RT)has been a challenge because of the ...Visible light microlasers are essential building blocks for integrated photonics.However,achieving low-threshold(μw),continuous-wave(CW)visible light lasing at room temperature(RT)has been a challenge because of the formidable requirement of population inversion at short wavelengths.Rare-earth(RE)-activated microcavities,featuring highquality factor(Q)and small mode volume of whispering gallery modes,offer a great opportunity for achieving infrared-to-visible upconversion(UC)lasing.Here,we report that batch-produced nano-glass composite(GC)microspheres incorporating RE-doped fluoride nanocrystals show efficient UC emissions.These multi-phase composite microspheres exhibit a high Q value(≥10^(5)),comparable to that of conventional multi-component glass microspheres.The UC lasing with pure red,green,and blue(RGB)emissions are demonstrated based on a highly efficient tapered fiber-microsphere system.More importantly,the GC microspheres manifest reduced(by 45%)lasing threshold and enhanced(more than four times)slope effciency.These characteristics,together with excellent long-term stability,suggest a promising solution to achieving highly robust,stand-alone,low-threshold,and versatile UC microlasers.展开更多
基金supported by the National Natural Science Foundation of China(62305244,52372003,62374112,62105078)Shandong Province Natural ScienceFoundation(ZR2021QE060,ZR2021QF009)+2 种基金Natural Science Foundation of Heilongjiang Province of China(ZD2023E004)Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2022QNRC001)Youth science and technology innovation team of Shandong Province institution of higher learning(2022KJ258).
文摘Visible light microlasers are essential building blocks for integrated photonics.However,achieving low-threshold(μw),continuous-wave(CW)visible light lasing at room temperature(RT)has been a challenge because of the formidable requirement of population inversion at short wavelengths.Rare-earth(RE)-activated microcavities,featuring highquality factor(Q)and small mode volume of whispering gallery modes,offer a great opportunity for achieving infrared-to-visible upconversion(UC)lasing.Here,we report that batch-produced nano-glass composite(GC)microspheres incorporating RE-doped fluoride nanocrystals show efficient UC emissions.These multi-phase composite microspheres exhibit a high Q value(≥10^(5)),comparable to that of conventional multi-component glass microspheres.The UC lasing with pure red,green,and blue(RGB)emissions are demonstrated based on a highly efficient tapered fiber-microsphere system.More importantly,the GC microspheres manifest reduced(by 45%)lasing threshold and enhanced(more than four times)slope effciency.These characteristics,together with excellent long-term stability,suggest a promising solution to achieving highly robust,stand-alone,low-threshold,and versatile UC microlasers.
