Magnetic polarons in type-II (Zn,Mn)Se/ZnTe quantum dots

ORAL

Abstract

We have studied magnetic polaron formation dynamics in (Zn,Mn)Se/ZnTe quantum dots$^{\mathrm{2}}$ (QDs) using time-resolved photoluminescence (TRPL) spectroscopy. The emitted light was spectrally and temporally analyzed; the emission spectra were recorded as function of time delay ($\Delta t)$ from the exciting laser pulse. The recombination time at $T=$10 K in our samples is 2.3 ns. The peak energy of the emission red shifts with increasing $\Delta t $due to the lowering of the hole-Mn spin complex (magnetic polaron) energy. From this shift we determined the magnetic polaron formation energy ($E_{MP})$ at $T=$10 K to be 20 meV, which is half the value observed in the ZnSe/(Zn,Mn)Te system studied previously.$^{\mathrm{3}} \quad E_{MP\thinspace }$decreases with increasing temperature, in contrast to the behavior of the ZnSe/(Zn,Mn)Te system$^{\mathrm{3}}$ in which $E_{MP}$ is temperature independent. These results are discussed in terms of a theoretical model. [2] L. Lee, et al., J. Cryst. Growth \textbf{378}, 222 (2013). [3] I. R. Sellers, et al., Phys. Rev. B \textbf{82}, 195320 (2010).

*This work is supported by DOE-BES, ONR and NSF

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Authors

  • J.R. Murphy

    • SUNY Buffalo

  • B. Barman

    • SUNY Buffalo

  • Y. Tsai

    • SUNY Buffalo

  • T. Scrace

    • SUNY Buffalo

  • J.M. Pientka

    • SUNY Buffalo

  • I. Zutic

    • SUNY Buffalo

  • B.D. McCombe

    • SUNY Buffalo

  • A. Petrou

    • SUNY Buffalo

  • A.N. Cartwright

    • SUNY Buffalo

  • W.C. Chou

    • National Chiao Tung University, Taiwan

  • M.H. Tsou

    • National Chiao Tung University, Taiwan

  • C.S. Yang

    • Graduate Institute of Electro-Optical Engineering, Tatung University, Taiwan

  • I.R. Sellers

    • University of Oklahoma

  • R. Oszwaldowski

    • South Dakota School of Mines and Technology

  • A.G. Petukhov

    • South Dakota School of Mines and Technology