Temperature dependence of stress birefringence in an elliptically clad fiber

The stress birefringence in a fiber with a three-component silica-glass elliptical cladding is found to be a strongly nonlinear function of temperature. The observed birefringence is a factor of 1.6 greater than that predicted from linear approximations of this dependence and estimates of the fiber material's properties. The fiber's birefrin-gence can be predicted from a linear extrapolation of the low-temperature data.