Frequency upconversion involving triads and quartets of ions in a Pr3+/Nd3+ codoped fluoroindate glass

Abstract

Frequency upconversion ͑UC͒ processes involving energy transfer ͑ET͒ among Nd 3ϩ and Pr 3ϩ ions in a fluoroindate glass are reported. In a first experiment, the excitation of Pr 3ϩ ͓transition 3 H 4 → 1 D 2 ͔ and of Nd 3ϩ ͓transition 4 I 9/2 →( 2 G 7/2 ϩ 4 G 5/2 )͔ was achieved with a dye laser operating in the 575-590 nm range. In a second experiment, the Nd 3ϩ ions were excited with the second harmonic of a Nd: YAG laser at 532 nm. The ET processes leading to UC in both experiments were studied by monitoring the blue fluorescence decay at 480 nm due to the transition 3 P 0 → 3 H 4 in Pr 3ϩ . In the more relevant UC process, quartets of ions ͑Nd-Nd-Pr-Pr͒ are excited due to absorption of three laser photons by two Nd 3ϩ ions which transfer their energy to two Pr 3ϩ ions. Each Pr 3ϩ ion promoted to the 3 P 0 level decays to the ground state emitting one photon in the blue region. This conclusion was achieved investigating the dependence of the UC fluorescence intensity as a function of laser intensity, samples concentrations, and temporal behavior of the UC signal. Other UC processes involving nonisoionic groups of three ions are also reported.

Phonon-assisted cooperative energy transfer and frequency upconversion in a Yb3+/Tb3+ codoped fluoroindate glass

“…4 Various UC processes that involve different RE ions have been demonstrated and indicate that FIG is a promising host material for UC based devices. [5][6][7][8][9][10] Besides choosing a good host material for RE ions, the efficiency for infrared-to-visible and ultraviolet light conversion can be improved if one uses a sensitizer to increase near-infrared absorption. In this case, the ytterbium (Yb 3ϩ ) ion has been used because it contains only one electronic transition inside the 4f subshell, which guarantees a large ground-state absorption cross section.…”

Surface-plasmon-enhanced frequency upconversion in Pr3+ doped tellurium-oxide glasses containing silver nanoparticles

“…This is clearer when energy levels closer to the surface plasmon resonance participate in the UC process. Finally, the present results suggest that the presence of silver nanoparticles may enhance UC processes of high order, such as the ones involving triads and quartets of Pr 3+ , 19,20 by a factor much larger than is shown here for ion pairs. …”

Energy transfer and frequency upconversion involving triads of Pr3+ ions in (Pr3+, Gd3+) doped fluoroindate glass

“…22͒ and Pr 3+ /Nd 3+ . 23 A process involving ET among three excited Er 3+ ions was used to construct a practical temperature sensor. 24 The studies of UC due to ET in fluoroindate glasses have demonstrated the large potential of these materials for devices because of their large transparency window, the low multiphonon emission rates, and the high fluorescence efficiency of RE ions hosted in these glasses.…”

“…14,15 In fluoride glasses, many ET processes were observed and successfully exploited. [3][4][5][16][17][18][19][20][21][22][23] For example, the efficient ET process in Nd 3+ -Pr 3+ pairs was exploited to obtain blue laser emission in fluorozirconate glass. 16 In fluoroindate glasses, besides the observation of ET involving RE pairs, [17][18][19][20] ET processes involving triads and quartets of ions were investigated in samples doped with Er 3+ ͑Ref.…”

“…24 The studies of UC due to ET in fluoroindate glasses have demonstrated the large potential of these materials for devices because of their large transparency window, the low multiphonon emission rates, and the high fluorescence efficiency of RE ions hosted in these glasses. [17][18][19][20][21][22][23] Furthermore, it is possible to incorporate large concentration of RE ions inside the glass matrix and as a consequence many efficient ET processes can be observed. Moreover, a method to fabria͒ Author to whom correspondence should be addressed; electronic mail: cid@df.ufpe.br cate waveguides on fluoroindate substrates was presented 25 and monomode fibers can be made with basis on fluoroindate glasses.…”