CINECA IRIS Institutional Research Information System

IRIS è l'Anagrafe della ricerca dell'Università degli Studi di Trento, e ha lo scopo di raccogliere, documentare, conservare e diffondere, anche ad accesso aperto, la produzione scientifica degli autori afferenti all'Università degli Studi di Trento.

Visible to near infrared down-conversion has been studied in Tm3+/Yb3+-codoped fluorozirconate glasses, namely ZBLA (57ZrF(4)-34BaF(2)-5LaF(3)-4AlF(3) in mol%) and ZLAG (70.2ZrF(4)-23.4LaF(3)-0.6AlF(3)-5.8GaF(3) in mol%). Upon blue excitation at 467 nm, Tm3+ doped glasses yield weak red at 650 nm and strong luminescence around 800 nm. With the addition of Yb3+, emission between 950 and 1100 nm from the Yb3+: F-2(5/2) -> F-2(7/2) transition was observed. This emission well matched with the band gap of crystalline silicium. The mechanism responsible for down-conversion in the Tm3+/Yb3+ ion-pair is a down-shifting process. The highest energy transfer efficiency eta(ETE) was 64.5% in ZBLA glasses doped with 0.75Tm(3+)/10Yb(3+); this efficiency was mainly limited by the strong Yb3+ to Tm3+ back energy transfer. eta(ETE) appeared to increase more rapidly with the addition of Yb3+ in ZLAG glasses, as already observed for the energy transfer in Pr3+/Yb3+ ion-pair. The origin of the difference between the two hosts is probably related to the distribution of rare-earth ions in the host matrix, as shown by molecular dynamics simulation.@ The Tm3+/Yb3+ system is found much less efficient that the Pr3+/Yb3+ one, because of less efficient quantum efficiency together with lower blue absorption of Tm3+ compared to Pr3+.

Blue to NIR down-conversion in Tm3+/Yb3+-codoped fluorozirconate glasses compared to Pr3+/Yb3+ ion-pair / Maalej, O; Lukowiak, A; Bouajaj, A; Chiasera, A; Righini, Gc; Ferrari, M; Boulard, B. - In: JOURNAL OF LUMINESCENCE. - ISSN 0022-2313. - 193:(2018), pp. 22-28. [10.1016/j.jlumin.2017.09.021]

Powered by IRIS-about IRIS-Utilizzo dei cookie

 Copyright © 2022