Subtle local structural variations in oxygen deficient niobium germanate thin film glasses as revealed by x-ray absorption spectroscopy

16th International Conference on X-ray Absorption Fine Structure

Sahiner, M.A.^1 ; Nabizadeh, A.^1 ; Rivella, D.^1 ; Cerqueira, L.^1 ; Hachlica, J.^1 ; Morea, R.^2 ; Gonzalo, J.^2 ; Woicik, J.C.^3

Seton Hall University, Physics Department, South Orange

NJ

07079, United States^1

Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, Madrid

28006, Spain^2

National Institute of Standards and Technology, Gaithersburg

MD

20899, United States^3

关键词: Local environments;    Nonlinear optical devices;    Optical characteristics;    Optical susceptibility;    Oxygen partial pressure;    Oxygen stoichiometry;    Structural variations;    Third order optical susceptibility;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012103/pdf
DOI  :  10.1088/1742-6596/712/1/012103

来源: IOP

【 摘 要 】

The local electronic and crystal structure of niobium-lead-germanate, Nb2O5-PbO- GeO2(NPG), glass thin films on silicon substrates were probed by XANES and EXAFS. NPG glasses are promising candidates for applications in nonlinear optical devices because they exhibit interesting optical characteristics such as high nonlinear third order optical susceptibility. In this work NPG glasses were prepared with pulsed laser deposition method with varying oxygen partial pressure to induce thin films with different oxygen stoichiometry. Previously, it was shown that oxygen stoichiometry has a very important effect to produce unusual high optical susceptibility. Detailed EXAFS and XANES analyses in a series of NPG thin films revealed the subtle variations in the local environment around Nb atoms and the Nb oxidation states caused by oxygen deficiencies.