Answers are grounded in this paper and cite their sources.
It is shown that zero polarisation mode dispersion can never be achieved in elliptical-core single-mode fibres by geometrical birefringence alone. To equalise the group delays of the two fundamental modes, stress-induced birefringence must be introduced to cancel, partly or completely, the geometrical birefringence, depending on the application.
No takes yet. Share an insight, caveat, or question.
Kin Seng Chiang (1985) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: