title: Cooperative downconversion in Yb3+/-RE3+ (RE=Tm or Pr) codoped lanthanum borogermanate glasses.
abstract: We report on cooperative downconversion in Yb(3+)-RE(3+) (RE=Tm or Pr) codoped lanthanum borogermanate glasses (LBG), which are capable of splitting a visible photon absorbed by Tm(3+) or Pr(3+) ions into two near-infrared photons. The results indicate that Pr(3+)-Yb(3+) is a more efficient ion couple than Tm(3+)-Yb(3+) in terms of cooperative downconversion. We have obtained a highest quantum yield of 165% and 138% for Pr(3+)-Yb(3+) and Tm(3+)-Yb(3+) codoped LBG glasses under 468 nm excitation, respectively. However, ultraviolet light excitation to the charge transfer band of Yb(3+) does not result in quantum splitting as rapid relaxation from the charge transfer band to 4f(13) levels of Yb(3+) dominates.
authors.affiliation: State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Liu
authors.forename: Yanbo
authors.initials: Y
authors.lastname: Qiao
authors.forename: Guoping
authors.initials: G
authors.lastname: Dong
authors.forename: Song
authors.initials: S
authors.lastname: Ye
authors.forename: Bin
authors.initials: B
authors.lastname: Zhu
authors.forename: Gandham
authors.initials: G
authors.lastname: Lakshminarayana
authors.forename: Danping
authors.initials: D
authors.lastname: Chen
authors.forename: Jianrong
authors.initials: J
authors.lastname: Qiu