Strong blue emission from Pr3+ ions through energy transfer process from Nd3+ to Pr3+ via Yb3+ in tellurite glass

Energy transfer excited upconversion emission in Nd3+/Pr3+-codped tellurite glass have been studied on pumping with 800 rum wavelength. The upconversion emission bands from Pr3+ ion are observed at the 488, 524, 546, 612, 647, 672, 708 and 723 nm due to the (P-3(0) + P-3(1)) -> H-3(4), P-3(1) -> H-3(5),P-3(0) -> H-3(5) P-3(0) -> H-3(6), P-3(0) -> F-3(2), P-3(1) -> F-3(3), P-3(0) -> F-3(3) and P-3(0) -> F-3(4) transitions, respectively. The addition of ytterbium ions (Yb3+) on the upconversion emission intensity is also studied and result shows an eight times enhancement in the upconversion intensity at 488 nut from Pr3+ ions. The pump power and concentration dependence studies are also made. It is found that Yb3+, ions transfer its excitation energy to Nd3+, from which it goes to Pr3+. No direct transfer to Pr3+ is seen. This is verified by codoping Nd3+ and Pr3+ into the host. (C) 2008 Elsevier B.V. All rights reserved.