Fibres that maintain a fundamental mode with fixed polarisation can be realised by the introduction of a large strain birefringence. A modal birefringence of 3 × 10−4 was achieved by differential thermal expansion in a germanosilicate fibre prepared from a circular preform by the exposed-cladding technique. Measurements of birefringence agree with earlier calculations.
No takes yet. Share an insight, caveat, or question.
Kaminow et al. (1979) studied this question.