Distribution of elements in Ge–Se bulk glasses and optical fibers detected by inductively coupled plasma atomic emission spectrometry

The elemental composition of Ge–Se glasses prepared by different methods and the distribution of Ge and Se along the bulk sample length are investigated by inductively coupled plasma atomic emission spectrometry. The estimated uncertainty of Ge and Se content measurement is 0.02–0.05 at.% (P = 0.95). To date, these results are the most accurate for determining the elemental composition of optical Ge-based chalcogenides. The minimum required mass of the analyzed glass samples does not exceed 1 mg. Partial phase separation in the Ge–Se system leads to a significant (±2 at.%) deviation of the chemical composition of Ge–Se glasses along the length of the bulk sample from the specified value. This is the first time that the elemental composition of single-index Ge–Se fibers along the fiber length has been studied. The rod drawing method allows the fabrication of optical fibers with composition deviation along the length of 0.03–0.05 at.%. In the case of drawing by the crucible method, the deviations of the fiber composition can reach 0.16 at.% compared with the initial glass sample.