Fast photoluminescence decay processes of doped ZnO phosphors

• DOI: 10.1007/s00340-007-2582-1
• Publication Date: 2007-03-01T18:58:04Z
• Authors: A. Gupta; N.K. Verma; H.S. Bhatti
• Keywords: 0103 physical sciences; 02 engineering and technology; 0210 nano-technology; 01 natural sciences; 7. Clean energy

Singly and doubly doped CaS phosphors have been synthesized using the flux method. Excited-state lifetime measurements have been carried out for CaS doped with Mn and quencher impurities (Fe or Co or Ni) having doping concentrations 0.05–0.70% by weight, using pulsed-UV laser (nitrogen laser) as the excitation source having pulse width (10 ns) and peak power (200 kW per pulse). Laser-induced photoluminescence has been observed in CaS-doped phosphors when these phosphors were excited by the pulsed-UV N2 laser radiation. Owing to the downconversion phenomenon, fast photoluminescence emission in the visible region is recorded in microseconds time domain for CaS:Mn, whereas in case of CaS:Mn:Ni, shortest component of lifetime values reduces to nanoseconds time domain.