Dielectric matrix imposed stress–strain effect on photoluminescence of Ge nanocrystals

• Published in: Solid state communications Vol. 149; no. 15; pp. 598 - 601
• Main Authors: Wu, R.S., Luo, X.F., Yuan, C.L., Zhang, Z.R.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.04.2009; Elsevier
• Subjects: A. Dielectric thin films; A. Nanocrystals; Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Properties and materials; E. Photoluminescence; Exact sciences and technology; Nanocrystals and nanoparticles; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; 78.55.-m; 77.55.+f; A. Dielectric thin films; E. Photoluminescence; A. Nanocrystals; 61.46.Hk; D. Properties and materials; Interface defect; Photoluminescence; Pulsed laser deposition; XRD; Bond lengths; Thin films; Lutetium oxides; Compressive stress; Transmission electron microscopy; Silicon oxides; Stress effects; Germanium; Nanocrystal
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2009.01.031

Ge nanocrystals embedded in SiO 2 and Lu 2O 3 matrices were fabricated using the pulsed laser deposition method and investigated using high-resolution transmission electron microscopy, X-ray diffractometry and photoluminescence spectroscopy. X-ray diffractometry and Fullprof computer program clearly revealed the bond lengths of Ge nanocrystals embedded in Lu 2O 3 matrix is smaller than that in SiO 2 matrix, which can be attributed to the greater compressive stress exerted on Ge nanocrystals by the Lu 2O 3 matrix. The greater compressive stress will lead to much more defects induced at the interface of Ge nanocrystals and thus enhance the intensity of photoluminescence. The findings presented here indicate that the matrix environment of the nanocrystals plays a significant role in the photoluminescence property.