The Sensitized Near Infrared Luminescence Of Ho³⁺ And Tm³⁺ Ions Excited By Blue Light In YAG Matrix

The near infrared(NIR)luminescence around 2.0nm is located in the atmospheric transmission window.The NIR luminescence around 2.0?m has important application prospects in radar system,infrared remote sensing and laser ranging because of its advantages such as strong penetrability to atmosphere and smoke,good secrecy and safety to human eyes.In recent years,the Ho3+,Tm3+ doped NIR luminescent materials,which provide luminescence around 2.0?m have aroused great interest of researchers.This kind of near infrared luminescent materials is used in medical treatment,human eye safety remote detection system and so on.Ce3+/Er3+/Ho3+ tri-doped and Mn4+/Er3+/Tm3+ tri-doped Y3Al5O12(YAG)samples were prepared in this work.The characteristics and mechanism of these two kind NIR luminescence materials doped with two kind of different rare earth ions and transition metal ion were studied as well.The main research content are as follow:1.Mn4+/Tm3+ co-doped and Mn4+/Er3+/Tm3+ tri-doped samples were prepared through molten salt method.The NIR emission spectra of all samples were measured under the excitation of 455nm laser.The energy transfer in Mn4+/Tm3+ co-doped and Mn4+/Er3+/Tm3+ tri-doped samples were studied in this work.It is found that both Mn4+ and Mn4+/Er3+ ion-pair can sensitize the 1600-2000nm NIR luminescence of Tm3+ through different sensitization channels.2.Ce3+/Er3+/Ho3+ tri-doped samples were prepared through coprecipitation-melted salt method in this work.The NIR emission spectra of all samples were measured under the excitation of 455nm laser.The doping concentration of Ho3+ ions was adjusted in these Era+/Ce3+co-doped YAG samples.It's found that the luminescence of Er3+ around 1532nm decreased,and the luminescence of Ho3+ around 2090nm increased.The Er3+ can be sensitized by Ce3+.Then after the energy transfer from Er3+ to Ho3+,the Er3+ located at 4I13/2 level excite the Ho3+located at ground state to 5I7 level.Meanwhile,the cross-relaxation between Ce3+,Er3+,Ho3+ can result more Ho3+ ions reach to the 5I7 level,and finally enhance the luminescence of Ho3+ at 2090nm.