Abstract
Recently it has been demonstrated that a continuously twisted photonic crystal fibre (PCF) with a "propeller-like" core, formed from three satellite subcores, supports a pair of non-degenerate helical Bloch modes whose dominant azimuthal harmonics have OAM order ℓ = ±1 [1]. Such a twisted system can be understood by realising that the guided light takes the form of a helical Bloch wave whose azimuthally periodic field pattern must spin with the structure. The non-degeneracy of the –1 and +1 OAM modes makes twisted PCF of particular interest because both the sign and magnitude of the OAM are preserved against external perturbations even over long fibre lengths. Here we report a more complex version of this structure that has six satellite subcores, and show experimentally that it supports four non-degenerate modes with OAM order ℓ = ±1 and ±2.
© 2015 IEEE
PDF ArticleMore Like This
P. Roth, G. K. L. Wong, M. H. Frosz, G. Ahmed, and P. St. J. Russell
cj_9_4 The European Conference on Lasers and Electro-Optics (CLEO/Europe) 2019
Rik Chattopadhyay and Shyamal Kumar Bhadra
JTu5A.71 Bragg Gratings, Photosensitivity and Poling in Glass Waveguides and Materials (BGPP) 2018
G. K. L. Wong, M. S. Kang, H. W. Lee, S. Burger, L. Zschiedrich, F. Biancalana, and P. St. J. Russell
FMG3 Frontiers in Optics (FiO) 2011