%0 Electronic Article %A R.D. Birch %K circularly birefringent helical fibres %K fabrication %K levels of circular birefringence %K structure %K single mode optical fibres %K polarisation maintaining fibres %K 633 nm %K operation %K helical-core circularly birefringent fibres %K characterisation %X A technique for fabricating helical-core circularly birefringent fibres is reported. Extremely high levels of circular birefringence are achieved (B = 2.1 × 10-4 at 633 nm). Because of its unique structure, this fibre remains single-mode up to V values of 25. %@ 0013-5194 %T Fabrication and characterisation of circularly birefringent helical fibres %B Electronics Letters %D January 1987 %V 23 %N 1 %P 50-52 %I Institution of Engineering and Technology %U https://digital-library.theiet.org/;jsessionid=2tkl0h8c0acfp.x-iet-live-01content/journals/10.1049/el_19870037 %G EN