Effect of codoping of Zn2+ ion on the upconversion of Er3+-Yb3+ codoped Y2O3 phosphor

The frequency upconversion emission from Er³⁺-Yb³⁺ codoped Y₂O₃ phosphor synthesized by low temperature, urea assisted combustion technique has been studied upon excitation at 980 nm diode laser. The effect of incorporation of Zn²⁺ ion on upconversion (UC) emission bands around 409 nm, 523 nm, 551 nm, 661 nm arises due to the transitions ²H_9/2 → ⁴I_15/2, ²H_11/2 → ⁴I_15/2, ⁴S_3/2 → ⁴I_15/2 and ⁴F_9/2 → ⁴I_15/2 of Er³⁺ ions have been investigated. The basic mechanism involved in UC process and reason of intensity enhancement on Zn²⁺ codoping have been explained by energy level structure and decay time analyses. The present study indicates that the developed phosphors may be of significant interest for use in photonic applications.