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Isoelectronic Centers in Quantum Dots and Photoluminescence Decay

  • Kiran G. Sonawane
  • Ch. Rajesh
  • Shailaja MahamuniEmail author
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 143)

Abstract

It is hypothesized that Te forms an isoelectronic trap in ZnSe. These isoelectronic centers show blue and green band luminescence at low temperature. Quantum confinement effects reveal isoelectronic trap related luminescence at room temperature in contrast to bulk ZnSe1 − yTey. To find the effect of these isoelectronic center on Mn2+ dd transition luminescence, Mn doped ZnSe0.99Te0.01 QDs are synthesized. Mn doped ZnSe shows dominating orange emission related to Mn2+ dd transitions. This Mn emission increases at the cost of band edge emission. Addition of Te as small as 1 % in ZnSe strongly quenches photoluminescence of Mn-doped ZnSe QDs showing predominance of Te-isoelectronic centers. Orange emission and near band edge luminescence in Mn doped ZnSe0.99Te0.01 are not correlated as they are in case of Mn-doped ZnSe QDs. Time resolved photoluminescence and photoluminescence excitation study revealed these isoelectronic center changes the recombination path ways. The changes in relaxation path ways are responsible for distinct emission behavior of ZnSe0.99Te0.01QDs.

Keywords

Quantum dots Isoelectronic doping Luminescence Time resolved photoluminescence 

Notes

Acknowledgments

KGS and CR are thankful to BRNS and ISRO-UOP for the financial support respectively. Authors are extremely thankful to Prof. N. Periasamy of TIFR for his interest in the work and several suggestions. We are also thankful to Ms. Madhuri of TIFR for help in recording the TRPL spectra. Authors are also thankful to D. S. T. Unit on Nanoscience, CNQS and D. S. T. FIST program for various characterization facilities.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Kiran G. Sonawane
    • 1
  • Ch. Rajesh
    • 1
  • Shailaja Mahamuni
    • 1
    Email author
  1. 1.Department of PhysicsUniversity of PunePuneIndia

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