Upconversion emission study of Er³⁺ doped CaMoO₄ phosphor

The infrared to visible upconversion emission in Er³⁺ doped CaMoO₄ phosphor has been investigated upon 980 nm diode laser excitation. The X-ray diffraction analysis reveals well crystalline nature and tetragonal phase structure of the prepared phosphor annealed at 800 °C. The Er³⁺ doped CaMoO₄ phosphor has shown intense green upconversion emission upon 980 nm didode laser excitation. The green emission bands at 530 nm and 552 nm corresponds to the ²H_11/2→⁴I_15/2 and ⁴S_3/2→⁴I_15/2 electronic transitions, respectively of Er³⁺ ion. The very weak red emission band around 656 nm is assigned to the ⁴F_9/2→⁴I_15/2 transition of Er³⁺ ion. The CIE color coordinate exhibits the emission color in intense green region, indicating the use of present phosphor in display device applications.