Table 1 Properties of the used glasses and glass preforms.

From: Fused silica optical fibers with graded index nanostructured core

Parameter

Glass type

low index

step-index preform

core

cladding

SK1310

Ge-doped F300

F300

Refractive index, ne

1.4609

1.47207

1.46007

Initial diameter [mm]

N/A

18.4

24

GeO2 concentration [% mol]

0

8.5

0

Final rod diameter [mm]

0.45

0.45

Effective GeO2 conc. [% mol]

0

4.9% mol

Effective ne

1.4609

1.4678