Laboratoire H Curien, UMR CNRS 5516, Université Jean Monnet, 18 Rue du Pr.Benoît Lauras 42000, Saint-Etienne, France.
J Phys Condens Matter. 2011 Jan 12;23(1):015903. doi: 10.1088/0953-8984/23/1/015903. Epub 2010 Dec 6.
We present an experimental investigation regarding the changes induced by the Ge doping level on the emission profile of the germanium lone pair center (GLPC) in Ge doped silica. The investigated samples have been produced by the sol-gel method and by plasma-activated chemical vapor deposition and have doping levels up to 20% by weight. The recorded photoluminescence spectra show that the GLPC emission profile is the same when the Ge content is lower than ∼ 1% by weight, whereas it changes for higher doping levels. We have also performed Raman scattering measurements that show the decrease of the D1 Raman band at 490 cm( - 1) when the Ge content is higher than 1% by weight. The data suggest that both changes can be related to matrix modifications. These findings improve our knowledge of the matrix effects on the physical properties of the point defects and, in particular, for the GLPC they show that variations in their emission properties are induced by the presence of a second Ge atom close to the defect within a sphere with a radius of about 2 nm.
我们进行了一项实验研究，探讨了锗掺杂水平对锗孤对中心（GLPC）在锗掺杂二氧化硅中发射谱的影响。所研究的样品是通过溶胶-凝胶法和等离子体辅助化学气相沉积法制备的，掺杂水平高达 20%（重量）。记录的光致发光谱表明，当 Ge 含量低于约 1%（重量）时，GLPC 发射谱是相同的，而当掺杂水平更高时，发射谱会发生变化。我们还进行了拉曼散射测量，结果表明当 Ge 含量高于 1%（重量）时，490cm(-1)处的 D1 拉曼带会减少。这些数据表明，这两种变化都可以与基质改性有关。这些发现提高了我们对点缺陷物理性质的基质效应的认识，特别是对于 GLPC，它们表明，在一个半径约为 2nm 的球体中，靠近缺陷的第二个 Ge 原子的存在会导致其发射性质的变化。
