|
|||||
|
|
Thermal stress induced birefringence in double cladding fiber with non-circular inner cladding |
|
| Authors: | Dan Lu Tingwu Ge Jian Wu Kun Xu Jintong Lin |
| Affiliation: | 1. Key Laboratory of Optical Communication &2. Lightwave Technologies, Ministry of Education, Beijing University of Posts and Telecommunications , Beijing 100876, P.R. China ludann@sina.com;4. Lightwave Technologies, Ministry of Education, Beijing University of Posts and Telecommunications , Beijing 100876, P.R. China |
| Abstract: | Thermal stress induced birefringence due to the thermoelastic difference between the outer cladding and the non-circular inner cladding of a double cladding fiber (DCF) is theoretically investigated. A modified slab model is proposed to estimate the influence of the outer cladding on the birefringence property of the core. Numerical simulation is carried out to investigate the thermoelastic and geometric contributions of the cladding to thermal induced birefringence in rectangular and D-shaped ytterbium-doped DCFs. The thermoelastic relations deduced in the modified slab model are also qualitatively verified. Research shows that the influence of the outer cladding on the thermal-induced birefringence in DCF varies greatly depending on the choice of outer cladding materials, inner cladding shapes and temperature variation. |
| Keywords: | double cladding fiber fiber laser thermal stress birefringence polarization |