[1] XU Jian-ping, SHI Shao-bo, ZHANG Xiao-song and LI Lan,Journal of Optoelectronics Laser 21, 1593 (2010). (inChinese)
[2] ZHANG Xiao-Song, LI Lan, HUANG Qing-song, ZHANGGao-feng, XU Jian-ping, XUAN Rong-wei and WEI Fengwei,Journal of Optoelectronics Laser 22, 1 (2011). (inChinese)
[3] X. W. Zhang and J. B. Xia, Chin. J. Semiconductors 27, 2094(2006). (in Chinese)
[4] Jiangtao Hu, Lin-wang Wang, Liang-shi Li, Weidong Yang and A. Paul Alivisatos, J. Phys. Chem. B 106, 2447 (2002).
[5] X. W. Zhang, Y. H. Zhu and J. B. Xia, Physica E 33, 376(2006).
[6] J. I. Climente, M. Royo, J. L. Movilla and J. Planelles, Phys.Rev. B 79, 161301 (2009).
[7] Ci L. Fai, V. Teboul, A. Monteil, S.Maabou and I.Nsangou, Condensed Matter Physics 8, 639 (2005).
[8] F. Comas, N. Studart and G. E. Marques, Solid State Commun.130, 477 (2004).
[9] J. L. Xiao and C. L. Zhao, Superlattices Microstruct. 49, 9(2011).
[10] J. L. Xiao and Z. H. Ding, J. Low Temp. Phys. 163, 302(2011).
[11] J. Huybrechts, J. Phys. C: Solid State Phys. 9, L211 (1976).
[12] T. D. Lee, F. M. Low and D. Pines, Phys. Rev. 90, 297 (1953).
[13] M. A. Brummell, R. J. Nicholas, M. A. Hopkins, J. J. Harris and C. T. Foxon, Phys. Rev. Lett. 58, 77 (1987).